arch/x86/xen/pci-swiotlb-xen.c:96:1: warning: Using plain integer as NULL pointer
arch/x86/xen/pci-swiotlb-xen.c:96:1: warning: Using plain integer as NULL pointer
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
With this patch we provide the functionality to initialize the
Xen-SWIOTLB late in the bootup cycle - specifically for
Xen PCI-frontend. We still will work if the user had
supplied 'iommu=soft' on the Linux command line.
Note: We cannot depend on after_bootmem to automatically
determine whether this is early or not. This is because
when PCI IOMMUs are initialized it is after after_bootmem but
before a lot of "other" subsystems are initialized.
CC: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
[v1: Fix smatch warnings]
[v2: Added check for xen_swiotlb]
[v3: Rebased with new xen-swiotlb changes]
[v4: squashed xen/swiotlb: Depending on after_bootmem is not correct in]
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If the caller passes a valid kmap_op to m2p_add_override, we use
kmap_op->dev_bus_addr to store the original mfn, but dev_bus_addr is
part of the interface with Xen and if we are batching the hypercalls it
might not have been written by the hypervisor yet. That means that later
on Xen will write to it and we'll think that the original mfn is
actually what Xen has written to it.
Rather than "stealing" struct members from kmap_op, keep using
page->index to store the original mfn and add another parameter to
m2p_remove_override to get the corresponding kmap_op instead.
It is now responsibility of the caller to keep track of which kmap_op
corresponds to a particular page in the m2p_override (gntdev, the only
user of this interface that passes a valid kmap_op, is already doing that).
CC: stable@kernel.org
Reported-and-Tested-By: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* stable/128gb.v5.1:
xen/mmu: If the revector fails, don't attempt to revector anything else.
xen/p2m: When revectoring deal with holes in the P2M array.
xen/mmu: Release just the MFN list, not MFN list and part of pagetables.
xen/mmu: Remove from __ka space PMD entries for pagetables.
xen/mmu: Copy and revector the P2M tree.
xen/p2m: Add logic to revector a P2M tree to use __va leafs.
xen/mmu: Recycle the Xen provided L4, L3, and L2 pages
xen/mmu: For 64-bit do not call xen_map_identity_early
xen/mmu: use copy_page instead of memcpy.
xen/mmu: Provide comments describing the _ka and _va aliasing issue
xen/mmu: The xen_setup_kernel_pagetable doesn't need to return anything.
Revert "xen/x86: Workaround 64-bit hypervisor and 32-bit initial domain." and "xen/x86: Use memblock_reserve for sensitive areas."
xen/x86: Workaround 64-bit hypervisor and 32-bit initial domain.
xen/x86: Use memblock_reserve for sensitive areas.
xen/p2m: Fix the comment describing the P2M tree.
Conflicts:
arch/x86/xen/mmu.c
The pagetable_init is the old xen_pagetable_setup_done and xen_pagetable_setup_start
rolled in one.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'x86/platform' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (9690 commits)
x86: Document x86_init.paging.pagetable_init()
x86: xen: Cleanup and remove x86_init.paging.pagetable_setup_done()
x86: Move paging_init() call to x86_init.paging.pagetable_init()
x86: Rename pagetable_setup_start() to pagetable_init()
x86: Remove base argument from x86_init.paging.pagetable_setup_start
Linux 3.6-rc5
HID: tpkbd: work even if the new Lenovo Keyboard driver is not configured
Remove user-triggerable BUG from mpol_to_str
xen/pciback: Fix proper FLR steps.
uml: fix compile error in deliver_alarm()
dj: memory scribble in logi_dj
Fix order of arguments to compat_put_time[spec|val]
xen: Use correct masking in xen_swiotlb_alloc_coherent.
xen: fix logical error in tlb flushing
xen/p2m: Fix one-off error in checking the P2M tree directory.
powerpc: Don't use __put_user() in patch_instruction
powerpc: Make sure IPI handlers see data written by IPI senders
powerpc: Restore correct DSCR in context switch
powerpc: Fix DSCR inheritance in copy_thread()
powerpc: Keep thread.dscr and thread.dscr_inherit in sync
...
At this stage x86_init.paging.pagetable_setup_done is only used in the
XEN case. Move its content in the x86_init.paging.pagetable_init setup
function and remove the now unused x86_init.paging.pagetable_setup_done
remaining infrastructure.
Signed-off-by: Attilio Rao <attilio.rao@citrix.com>
Acked-by: <konrad.wilk@oracle.com>
Cc: <Ian.Campbell@citrix.com>
Cc: <Stefano.Stabellini@eu.citrix.com>
Cc: <xen-devel@lists.xensource.com>
Link: http://lkml.kernel.org/r/1345580561-8506-5-git-send-email-attilio.rao@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Move the paging_init() call to the platform specific pagetable_init()
function, so we can get rid of the extra pagetable_setup_done()
function pointer.
Signed-off-by: Attilio Rao <attilio.rao@citrix.com>
Acked-by: <konrad.wilk@oracle.com>
Cc: <Ian.Campbell@citrix.com>
Cc: <Stefano.Stabellini@eu.citrix.com>
Cc: <xen-devel@lists.xensource.com>
Link: http://lkml.kernel.org/r/1345580561-8506-4-git-send-email-attilio.rao@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In preparation for unifying the pagetable_setup_start() and
pagetable_setup_done() setup functions, rename appropriately all the
infrastructure related to pagetable_setup_start().
Signed-off-by: Attilio Rao <attilio.rao@citrix.com>
Ackedd-by: <konrad.wilk@oracle.com>
Cc: <Ian.Campbell@citrix.com>
Cc: <Stefano.Stabellini@eu.citrix.com>
Cc: <xen-devel@lists.xensource.com>
Link: http://lkml.kernel.org/r/1345580561-8506-3-git-send-email-attilio.rao@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We either use swapper_pg_dir or the argument is unused. Preparatory
patch to simplify platform pagetable setup further.
Signed-off-by: Attilio Rao <attilio.rao@citrix.com>
Ackedb-by: <konrad.wilk@oracle.com>
Cc: <Ian.Campbell@citrix.com>
Cc: <Stefano.Stabellini@eu.citrix.com>
Cc: <xen-devel@lists.xensource.com>
Link: http://lkml.kernel.org/r/1345580561-8506-2-git-send-email-attilio.rao@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Callers of xen_remap_domain_range() need to know if the remap failed
because frame is currently paged out. So they can retry the remap
later on. Return -ENOENT in this case.
This assumes that the error codes returned by Xen are a subset of
those used by the kernel. It is unclear if this is defined as part of
the hypercall ABI.
Acked-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
While TLB_FLUSH_ALL gets passed as 'end' argument to
flush_tlb_others(), the Xen code was made to check its 'start'
parameter. That may give a incorrect op.cmd to MMUEXT_INVLPG_MULTI
instead of MMUEXT_TLB_FLUSH_MULTI. Then it causes some page can not
be flushed from TLB.
This patch fixed this issue.
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Alex Shi <alex.shi@intel.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Yongjie Ren <yongjie.ren@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* commit '4cb38750d49010ae72e718d46605ac9ba5a851b4': (6849 commits)
bcma: fix invalid PMU chip control masks
[libata] pata_cmd64x: whitespace cleanup
libata-acpi: fix up for acpi_pm_device_sleep_state API
sata_dwc_460ex: device tree may specify dma_channel
ahci, trivial: fixed coding style issues related to braces
ahci_platform: add hibernation callbacks
libata-eh.c: local functions should not be exposed globally
libata-transport.c: local functions should not be exposed globally
sata_dwc_460ex: support hardreset
ata: use module_pci_driver
drivers/ata/pata_pcmcia.c: adjust suspicious bit operation
pata_imx: Convert to clk_prepare_enable/clk_disable_unprepare
ahci: Enable SB600 64bit DMA on MSI K9AGM2 (MS-7327) v2
[libata] Prevent interface errors with Seagate FreeAgent GoFlex
drivers/acpi/glue: revert accidental license-related 6b66d95895 bits
libata-acpi: add missing inlines in libata.h
i2c-omap: Add support for I2C_M_STOP message flag
i2c: Fall back to emulated SMBus if the operation isn't supported natively
i2c: Add SCCB support
i2c-tiny-usb: Add support for the Robofuzz OSIF USB/I2C converter
...
We would traverse the full P2M top directory (from 0->MAX_DOMAIN_PAGES
inclusive) when trying to figure out whether we can re-use some of the
P2M middle leafs.
Which meant that if the kernel was compiled with MAX_DOMAIN_PAGES=512
we would try to use the 512th entry. Fortunately for us the p2m_top_index
has a check for this:
BUG_ON(pfn >= MAX_P2M_PFN);
which we hit and saw this:
(XEN) domain_crash_sync called from entry.S
(XEN) Domain 0 (vcpu#0) crashed on cpu#0:
(XEN) ----[ Xen-4.1.2-OVM x86_64 debug=n Tainted: C ]----
(XEN) CPU: 0
(XEN) RIP: e033:[<ffffffff819cadeb>]
(XEN) RFLAGS: 0000000000000212 EM: 1 CONTEXT: pv guest
(XEN) rax: ffffffff81db5000 rbx: ffffffff81db4000 rcx: 0000000000000000
(XEN) rdx: 0000000000480211 rsi: 0000000000000000 rdi: ffffffff81db4000
(XEN) rbp: ffffffff81793db8 rsp: ffffffff81793d38 r8: 0000000008000000
(XEN) r9: 4000000000000000 r10: 0000000000000000 r11: ffffffff81db7000
(XEN) r12: 0000000000000ff8 r13: ffffffff81df1ff8 r14: ffffffff81db6000
(XEN) r15: 0000000000000ff8 cr0: 000000008005003b cr4: 00000000000026f0
(XEN) cr3: 0000000661795000 cr2: 0000000000000000
Fixes-Oracle-Bug: 14570662
CC: stable@vger.kernel.org # only for v3.5
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If the P2M revectoring would fail, we would try to continue on by
cleaning the PMD for L1 (PTE) page-tables. The xen_cleanhighmap
is greedy and erases the PMD on both boundaries. Since the P2M
array can share the PMD, we would wipe out part of the __ka
that is still used in the P2M tree to point to P2M leafs.
This fixes it by bypassing the revectoring and continuing on.
If the revector fails, a nice WARN is printed so we can still
troubleshoot this.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When we free the PFNs and then subsequently populate them back
during bootup:
Freeing 20000-20200 pfn range: 512 pages freed
1-1 mapping on 20000->20200
Freeing 40000-40200 pfn range: 512 pages freed
1-1 mapping on 40000->40200
Freeing bad80-badf4 pfn range: 116 pages freed
1-1 mapping on bad80->badf4
Freeing badf6-bae7f pfn range: 137 pages freed
1-1 mapping on badf6->bae7f
Freeing bb000-100000 pfn range: 282624 pages freed
1-1 mapping on bb000->100000
Released 283999 pages of unused memory
Set 283999 page(s) to 1-1 mapping
Populating 1acb8a-1f20e9 pfn range: 283999 pages added
We end up having the P2M array (that is the one that was
grafted on the P2M tree) filled with IDENTITY_FRAME or
INVALID_P2M_ENTRY) entries. The patch titled
"xen/p2m: Reuse existing P2M leafs if they are filled with 1:1 PFNs or INVALID."
recycles said slots and replaces the P2M tree leaf's with
&mfn_list[xx] with p2m_identity or p2m_missing.
And re-uses the P2M array sections for other P2M tree leaf's.
For the above mentioned bootup excerpt, the PFNs at
0x20000->0x20200 are going to be IDENTITY based:
P2M[0][256][0] -> P2M[0][257][0] get turned in IDENTITY_FRAME.
We can re-use that and replace P2M[0][256] to point to p2m_identity.
The "old" page (the grafted P2M array provided by Xen) that was at
P2M[0][256] gets put somewhere else. Specifically at P2M[6][358],
b/c when we populate back:
Populating 1acb8a-1f20e9 pfn range: 283999 pages added
we fill P2M[6][358][0] (and P2M[6][358], P2M[6][359], ...) with
the new MFNs.
That is all OK, except when we revector we assume that the PFN
count would be the same in the grafted P2M array and in the
newly allocated. Since that is no longer the case, as we have
holes in the P2M that point to p2m_missing or p2m_identity we
have to take that into account.
[v2: Check for overflow]
[v3: Move within the __va check]
[v4: Fix the computation]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We call memblock_reserve for [start of mfn list] -> [PMD aligned end
of mfn list] instead of <start of mfn list> -> <page aligned end of mfn list].
This has the disastrous effect that if at bootup the end of mfn_list is
not PMD aligned we end up returning to memblock parts of the region
past the mfn_list array. And those parts are the PTE tables with
the disastrous effect of seeing this at bootup:
Write protecting the kernel read-only data: 10240k
Freeing unused kernel memory: 1860k freed
Freeing unused kernel memory: 200k freed
(XEN) mm.c:2429:d0 Bad type (saw 1400000000000002 != exp 7000000000000000) for mfn 116a80 (pfn 14e26)
...
(XEN) mm.c:908:d0 Error getting mfn 116a83 (pfn 14e2a) from L1 entry 8000000116a83067 for l1e_owner=0, pg_owner=0
(XEN) mm.c:908:d0 Error getting mfn 4040 (pfn 5555555555555555) from L1 entry 0000000004040601 for l1e_owner=0, pg_owner=0
.. and so on.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Please first read the description in "xen/mmu: Copy and revector the
P2M tree."
At this stage, the __ka address space (which is what the old
P2M tree was using) is partially disassembled. The cleanup_highmap
has removed the PMD entries from 0-16MB and anything past _brk_end
up to the max_pfn_mapped (which is the end of the ramdisk).
The xen_remove_p2m_tree and code around has ripped out the __ka for
the old P2M array.
Here we continue on doing it to where the Xen page-tables were.
It is safe to do it, as the page-tables are addressed using __va.
For good measure we delete anything that is within MODULES_VADDR
and up to the end of the PMD.
At this point the __ka only contains PMD entries for the start
of the kernel up to __brk.
[v1: Per Stefano's suggestion wrapped the MODULES_VADDR in debug]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Please first read the description in "xen/p2m: Add logic to revector a
P2M tree to use __va leafs" patch.
The 'xen_revector_p2m_tree()' function allocates a new P2M tree
copies the contents of the old one in it, and returns the new one.
At this stage, the __ka address space (which is what the old
P2M tree was using) is partially disassembled. The cleanup_highmap
has removed the PMD entries from 0-16MB and anything past _brk_end
up to the max_pfn_mapped (which is the end of the ramdisk).
We have revectored the P2M tree (and the one for save/restore as well)
to use new shiny __va address to new MFNs. The xen_start_info
has been taken care of already in 'xen_setup_kernel_pagetable()' and
xen_start_info->shared_info in 'xen_setup_shared_info()', so
we are free to roam and delete PMD entries - which is exactly what
we are going to do. We rip out the __ka for the old P2M array.
[v1: Fix smatch warnings]
[v2: memset was doing 0 instead of 0xff]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
During bootup Xen supplies us with a P2M array. It sticks
it right after the ramdisk, as can be seen with a 128GB PV guest:
(certain parts removed for clarity):
xc_dom_build_image: called
xc_dom_alloc_segment: kernel : 0xffffffff81000000 -> 0xffffffff81e43000 (pfn 0x1000 + 0xe43 pages)
xc_dom_pfn_to_ptr: domU mapping: pfn 0x1000+0xe43 at 0x7f097d8bf000
xc_dom_alloc_segment: ramdisk : 0xffffffff81e43000 -> 0xffffffff925c7000 (pfn 0x1e43 + 0x10784 pages)
xc_dom_pfn_to_ptr: domU mapping: pfn 0x1e43+0x10784 at 0x7f0952dd2000
xc_dom_alloc_segment: phys2mach : 0xffffffff925c7000 -> 0xffffffffa25c7000 (pfn 0x125c7 + 0x10000 pages)
xc_dom_pfn_to_ptr: domU mapping: pfn 0x125c7+0x10000 at 0x7f0942dd2000
xc_dom_alloc_page : start info : 0xffffffffa25c7000 (pfn 0x225c7)
xc_dom_alloc_page : xenstore : 0xffffffffa25c8000 (pfn 0x225c8)
xc_dom_alloc_page : console : 0xffffffffa25c9000 (pfn 0x225c9)
nr_page_tables: 0x0000ffffffffffff/48: 0xffff000000000000 -> 0xffffffffffffffff, 1 table(s)
nr_page_tables: 0x0000007fffffffff/39: 0xffffff8000000000 -> 0xffffffffffffffff, 1 table(s)
nr_page_tables: 0x000000003fffffff/30: 0xffffffff80000000 -> 0xffffffffbfffffff, 1 table(s)
nr_page_tables: 0x00000000001fffff/21: 0xffffffff80000000 -> 0xffffffffa27fffff, 276 table(s)
xc_dom_alloc_segment: page tables : 0xffffffffa25ca000 -> 0xffffffffa26e1000 (pfn 0x225ca + 0x117 pages)
xc_dom_pfn_to_ptr: domU mapping: pfn 0x225ca+0x117 at 0x7f097d7a8000
xc_dom_alloc_page : boot stack : 0xffffffffa26e1000 (pfn 0x226e1)
xc_dom_build_image : virt_alloc_end : 0xffffffffa26e2000
xc_dom_build_image : virt_pgtab_end : 0xffffffffa2800000
So the physical memory and virtual (using __START_KERNEL_map addresses)
layout looks as so:
phys __ka
/------------\ /-------------------\
| 0 | empty | 0xffffffff80000000|
| .. | | .. |
| 16MB | <= kernel starts | 0xffffffff81000000|
| .. | | |
| 30MB | <= kernel ends => | 0xffffffff81e43000|
| .. | & ramdisk starts | .. |
| 293MB | <= ramdisk ends=> | 0xffffffff925c7000|
| .. | & P2M starts | .. |
| .. | | .. |
| 549MB | <= P2M ends => | 0xffffffffa25c7000|
| .. | start_info | 0xffffffffa25c7000|
| .. | xenstore | 0xffffffffa25c8000|
| .. | cosole | 0xffffffffa25c9000|
| 549MB | <= page tables => | 0xffffffffa25ca000|
| .. | | |
| 550MB | <= PGT end => | 0xffffffffa26e1000|
| .. | boot stack | |
\------------/ \-------------------/
As can be seen, the ramdisk, P2M and pagetables are taking
a bit of __ka addresses space. Which is a problem since the
MODULES_VADDR starts at 0xffffffffa0000000 - and P2M sits
right in there! This results during bootup with the inability to
load modules, with this error:
------------[ cut here ]------------
WARNING: at /home/konrad/ssd/linux/mm/vmalloc.c:106 vmap_page_range_noflush+0x2d9/0x370()
Call Trace:
[<ffffffff810719fa>] warn_slowpath_common+0x7a/0xb0
[<ffffffff81030279>] ? __raw_callee_save_xen_pmd_val+0x11/0x1e
[<ffffffff81071a45>] warn_slowpath_null+0x15/0x20
[<ffffffff81130b89>] vmap_page_range_noflush+0x2d9/0x370
[<ffffffff81130c4d>] map_vm_area+0x2d/0x50
[<ffffffff811326d0>] __vmalloc_node_range+0x160/0x250
[<ffffffff810c5369>] ? module_alloc_update_bounds+0x19/0x80
[<ffffffff810c6186>] ? load_module+0x66/0x19c0
[<ffffffff8105cadc>] module_alloc+0x5c/0x60
[<ffffffff810c5369>] ? module_alloc_update_bounds+0x19/0x80
[<ffffffff810c5369>] module_alloc_update_bounds+0x19/0x80
[<ffffffff810c70c3>] load_module+0xfa3/0x19c0
[<ffffffff812491f6>] ? security_file_permission+0x86/0x90
[<ffffffff810c7b3a>] sys_init_module+0x5a/0x220
[<ffffffff815ce339>] system_call_fastpath+0x16/0x1b
---[ end trace fd8f7704fdea0291 ]---
vmalloc: allocation failure, allocated 16384 of 20480 bytes
modprobe: page allocation failure: order:0, mode:0xd2
Since the __va and __ka are 1:1 up to MODULES_VADDR and
cleanup_highmap rids __ka of the ramdisk mapping, what
we want to do is similar - get rid of the P2M in the __ka
address space. There are two ways of fixing this:
1) All P2M lookups instead of using the __ka address would
use the __va address. This means we can safely erase from
__ka space the PMD pointers that point to the PFNs for
P2M array and be OK.
2). Allocate a new array, copy the existing P2M into it,
revector the P2M tree to use that, and return the old
P2M to the memory allocate. This has the advantage that
it sets the stage for using XEN_ELF_NOTE_INIT_P2M
feature. That feature allows us to set the exact virtual
address space we want for the P2M - and allows us to
boot as initial domain on large machines.
So we pick option 2).
This patch only lays the groundwork in the P2M code. The patch
that modifies the MMU is called "xen/mmu: Copy and revector the P2M tree."
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
As we are not using them. We end up only using the L1 pagetables
and grafting those to our page-tables.
[v1: Per Stefano's suggestion squashed two commits]
[v2: Per Stefano's suggestion simplified loop]
[v3: Fix smatch warnings]
[v4: Add more comments]
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
B/c we do not need it. During the startup the Xen provides
us with all the initial memory mapped that we need to function.
The initial memory mapped is up to the bootstack, which means
we can reference using __ka up to 4.f):
(from xen/interface/xen.h):
4. This the order of bootstrap elements in the initial virtual region:
a. relocated kernel image
b. initial ram disk [mod_start, mod_len]
c. list of allocated page frames [mfn_list, nr_pages]
d. start_info_t structure [register ESI (x86)]
e. bootstrap page tables [pt_base, CR3 (x86)]
f. bootstrap stack [register ESP (x86)]
(initial ram disk may be ommitted).
[v1: More comments in git commit]
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Which is that the level2_kernel_pgt (__ka virtual addresses)
and level2_ident_pgt (__va virtual address) contain the same
PMD entries. So if you modify a PTE in __ka, it will be reflected
in __va (and vice-versa).
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We don't need to return the new PGD - as we do not use it.
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This reverts commit 806c312e50 and
commit 59b294403e.
And also documents setup.c and why we want to do it that way, which
is that we tried to make the the memblock_reserve more selective so
that it would be clear what region is reserved. Sadly we ran
in the problem wherein on a 64-bit hypervisor with a 32-bit
initial domain, the pt_base has the cr3 value which is not
neccessarily where the pagetable starts! As Jan put it: "
Actually, the adjustment turns out to be correct: The page
tables for a 32-on-64 dom0 get allocated in the order "first L1",
"first L2", "first L3", so the offset to the page table base is
indeed 2. When reading xen/include/public/xen.h's comment
very strictly, this is not a violation (since there nothing is said
that the first thing in the page table space is pointed to by
pt_base; I admit that this seems to be implied though, namely
do I think that it is implied that the page table space is the
range [pt_base, pt_base + nt_pt_frames), whereas that
range here indeed is [pt_base - 2, pt_base - 2 + nt_pt_frames),
which - without a priori knowledge - the kernel would have
difficulty to figure out)." - so lets just fall back to the
easy way and reserve the whole region.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
arch/x86/xen/pci-swiotlb-xen.c:96:1: warning: Using plain integer as NULL pointer
arch/x86/xen/pci-swiotlb-xen.c:96:1: warning: Using plain integer as NULL pointer
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This patch removes the "return -ENOSYS" for auto_translated_physmap
guests from privcmd_mmap, thus it allows ARM guests to issue privcmd
mmap calls. However privcmd mmap calls are still going to fail for HVM
and hybrid guests on x86 because the xen_remap_domain_mfn_range
implementation is currently PV only.
Changes in v2:
- better commit message;
- return -EINVAL from xen_remap_domain_mfn_range if
auto_translated_physmap.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When we are finished with return PFNs to the hypervisor, then
populate it back, and also mark the E820 MMIO and E820 gaps
as IDENTITY_FRAMEs, we then call P2M to set areas that can
be used for ballooning. We were off by one, and ended up
over-writting a P2M entry that most likely was an IDENTITY_FRAME.
For example:
1-1 mapping on 40000->40200
1-1 mapping on bc558->bc5ac
1-1 mapping on bc5b4->bc8c5
1-1 mapping on bc8c6->bcb7c
1-1 mapping on bcd00->100000
Released 614 pages of unused memory
Set 277889 page(s) to 1-1 mapping
Populating 40200-40466 pfn range: 614 pages added
=> here we set from 40466 up to bc559 P2M tree to be
INVALID_P2M_ENTRY. We should have done it up to bc558.
The end result is that if anybody is trying to construct
a PTE for PFN bc558 they end up with ~PAGE_PRESENT.
CC: stable@vger.kernel.org
Reported-by-and-Tested-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We still patch SMP instructions to UP variants if we boot with a
single CPU, but not at any other time. In particular, not if we
unplug CPUs to return to a single cpu.
Paul McKenney points out:
mean offline overhead is 6251/48=130.2 milliseconds.
If I remove the alternatives_smp_switch() from the offline
path [...] the mean offline overhead is 550/42=13.1 milliseconds
Basically, we're never going to get those 120ms back, and the
code is pretty messy.
We get rid of:
1) The "smp-alt-once" boot option. It's actually "smp-alt-boot", the
documentation is wrong. It's now the default.
2) The skip_smp_alternatives flag used by suspend.
3) arch_disable_nonboot_cpus_begin() and arch_disable_nonboot_cpus_end()
which were only used to set this one flag.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paul.mckenney@us.ibm.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/87vcgwwive.fsf@rustcorp.com.au
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There is no need for those functions/variables to be visible. Make them
static and also fix the compile warnings of this sort:
drivers/xen/<some file>.c: warning: symbol '<blah>' was not declared. Should it be static?
Some of them just require including the header file that
declares the functions.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If a PV guest is booted the native SWIOTLB should not be
turned on. It does not help us (we don't have any PCI devices)
and it eats 64MB of good memory. In the case of PV guests
with PCI devices we need the Xen-SWIOTLB one.
[v1: Rewrite comment per Stefano's suggestion]
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Its pretty easy:
1). We only check to see if we need Xen SWIOTLB for PV guests.
2). If swiotlb=force or iommu=soft is set, then Xen SWIOTLB will
be enabled.
3). If it is an initial domain, then Xen SWIOTLB will be enabled.
4). Native SWIOTLB must be disabled for PV guests.
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If a 64-bit hypervisor is booted with a 32-bit initial domain,
the hypervisor deals with the initial domain as "compat" and
does some extra adjustments (like pagetables are 4 bytes instead
of 8). It also adjusts the xen_start_info->pt_base incorrectly.
When booted with a 32-bit hypervisor (32-bit initial domain):
..
(XEN) Start info: cf831000->cf83147c
(XEN) Page tables: cf832000->cf8b5000
..
[ 0.000000] PT: cf832000 (f832000)
[ 0.000000] Reserving PT: f832000->f8b5000
And with a 64-bit hypervisor:
(XEN) Start info: 00000000cf831000->00000000cf8314b4
(XEN) Page tables: 00000000cf832000->00000000cf8b6000
[ 0.000000] PT: cf834000 (f834000)
[ 0.000000] Reserving PT: f834000->f8b8000
To deal with this, we keep keep track of the highest physical
address we have reserved via memblock_reserve. If that address
does not overlap with pt_base, we have a gap which we reserve.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
instead of a big memblock_reserve. This way we can be more
selective in freeing regions (and it also makes it easier
to understand where is what).
[v1: Move the auto_translate_physmap to proper line]
[v2: Per Stefano suggestion add more comments]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
It mixed up the p2m_mid_missing with p2m_missing. Also
remove some extra spaces.
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If P2M leaf is completly packed with INVALID_P2M_ENTRY or with
1:1 PFNs (so IDENTITY_FRAME type PFNs), we can swap the P2M leaf
with either a p2m_missing or p2m_identity respectively. The old
page (which was created via extend_brk or was grafted on from the
mfn_list) can be re-used for setting new PFNs.
This also means we can remove git commit:
5bc6f9888d
xen/p2m: Reserve 8MB of _brk space for P2M leafs when populating back
which tried to fix this.
and make the amount that is required to be reserved much smaller.
CC: stable@vger.kernel.org # for 3.5 only.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* On machines with large MMIO/PCI E820 spaces we fail to boot b/c
we failed to pre-allocate large enough virtual space for extend_brk.
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Merge tag 'stable/for-linus-3.6-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull Xen fix from Konrad Rzeszutek Wilk:
"Way back in v3.5 we added a mechanism to populate back pages that were
released (they overlapped with MMIO regions), but neglected to reserve
the proper amount of virtual space for extend_brk to work properly.
Coincidentally some other commit aligned the _brk space to larger area
so I didn't trigger this until it was run on a machine with more than
2GB of MMIO space."
* On machines with large MMIO/PCI E820 spaces we fail to boot b/c
we failed to pre-allocate large enough virtual space for extend_brk.
* tag 'stable/for-linus-3.6-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/p2m: Reserve 8MB of _brk space for P2M leafs when populating back.
This reverts commit 00e37bdb01.
During shutdown of PVHVM guests with more than 2VCPUs on certain
machines we can hit the race where the replaced shared_info is not
replaced fast enough and the PV time clock retries reading the same
area over and over without any any success and is stuck in an
infinite loop.
Acked-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Compile events.c on ARM.
Parse, map and enable the IRQ to get event notifications from the device
tree (node "/xen").
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When we release pages back during bootup:
Freeing 9d-100 pfn range: 99 pages freed
Freeing 9cf36-9d0d2 pfn range: 412 pages freed
Freeing 9f6bd-9f6bf pfn range: 2 pages freed
Freeing 9f714-9f7bf pfn range: 171 pages freed
Freeing 9f7e0-9f7ff pfn range: 31 pages freed
Freeing 9f800-100000 pfn range: 395264 pages freed
Released 395979 pages of unused memory
We then try to populate those pages back. In the P2M tree however
the space for those leafs must be reserved - as such we use extend_brk.
We reserve 8MB of _brk space, which means we can fit over
1048576 PFNs - which is more than we should ever need.
Without this, on certain compilation of the kernel we would hit:
(XEN) domain_crash_sync called from entry.S
(XEN) CPU: 0
(XEN) RIP: e033:[<ffffffff818aad3b>]
(XEN) RFLAGS: 0000000000000206 EM: 1 CONTEXT: pv guest
(XEN) rax: ffffffff81a7c000 rbx: 000000000000003d rcx: 0000000000001000
(XEN) rdx: ffffffff81a7b000 rsi: 0000000000001000 rdi: 0000000000001000
(XEN) rbp: ffffffff81801cd8 rsp: ffffffff81801c98 r8: 0000000000100000
(XEN) r9: ffffffff81a7a000 r10: 0000000000000001 r11: 0000000000000003
(XEN) r12: 0000000000000004 r13: 0000000000000004 r14: 000000000000003d
(XEN) r15: 00000000000001e8 cr0: 000000008005003b cr4: 00000000000006f0
(XEN) cr3: 0000000125803000 cr2: 0000000000000000
(XEN) ds: 0000 es: 0000 fs: 0000 gs: 0000 ss: e02b cs: e033
(XEN) Guest stack trace from rsp=ffffffff81801c98:
.. which is extend_brk hitting a BUG_ON.
Interestingly enough, most of the time we are not going to hit this
b/c the _brk space is quite large (v3.5):
ffffffff81a25000 B __brk_base
ffffffff81e43000 B __brk_limit
= ~4MB.
vs earlier kernels (with this back-ported), the space is smaller:
ffffffff81a25000 B __brk_base
ffffffff81a7b000 B __brk_limit
= 344 kBytes.
where we would certainly hit this and hit extend_brk.
Note that git commit c3d93f8801
(xen: populate correct number of pages when across mem boundary (v2))
exposed this bug).
[v1: Made it 8MB of _brk space instead of 4MB per Jan's suggestion]
CC: stable@vger.kernel.org #only for 3.5
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This allows us in perf to have this:
99.67% [kernel] [k] xen_hypercall_sched_op
0.11% [kernel] [k] xen_hypercall_xen_version
instead of the borring ever-encompassing:
99.13% [kernel] [k] hypercall_page
[v2: Use a macro to define the name and skip]
[v3: Use balign per Jan's suggestion]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Pull x86/mm changes from Peter Anvin:
"The big change here is the patchset by Alex Shi to use INVLPG to flush
only the affected pages when we only need to flush a small page range.
It also removes the special INVALIDATE_TLB_VECTOR interrupts (32
vectors!) and replace it with an ordinary IPI function call."
Fix up trivial conflicts in arch/x86/include/asm/apic.h (added code next
to changed line)
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tlb: Fix build warning and crash when building for !SMP
x86/tlb: do flush_tlb_kernel_range by 'invlpg'
x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR
x86/tlb: enable tlb flush range support for x86
mm/mmu_gather: enable tlb flush range in generic mmu_gather
x86/tlb: add tlb_flushall_shift knob into debugfs
x86/tlb: add tlb_flushall_shift for specific CPU
x86/tlb: fall back to flush all when meet a THP large page
x86/flush_tlb: try flush_tlb_single one by one in flush_tlb_range
x86/tlb_info: get last level TLB entry number of CPU
x86: Add read_mostly declaration/definition to variables from smp.h
x86: Define early read-mostly per-cpu macros
* Performance improvement to lower the amount of traps the hypervisor
has to do 32-bit guests. Mainly for setting PTE entries and updating
TLS descriptors.
* MCE polling driver to collect hypervisor MCE buffer and present them to
/dev/mcelog.
* Physical CPU online/offline support. When an privileged guest is booted
it is present with virtual CPUs, which might have an 1:1 to physical
CPUs but usually don't. This provides mechanism to offline/online physical
CPUs.
Bug-fixes for:
* Coverity found fixes in the console and ACPI processor driver.
* PVonHVM kexec fixes along with some cleanups.
* Pages that fall within E820 gaps and non-RAM regions (and had been
released to hypervisor) would be populated back, but potentially in
non-RAM regions.
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Merge tag 'stable/for-linus-3.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull Xen update from Konrad Rzeszutek Wilk:
"Features:
* Performance improvement to lower the amount of traps the hypervisor
has to do 32-bit guests. Mainly for setting PTE entries and
updating TLS descriptors.
* MCE polling driver to collect hypervisor MCE buffer and present
them to /dev/mcelog.
* Physical CPU online/offline support. When an privileged guest is
booted it is present with virtual CPUs, which might have an 1:1 to
physical CPUs but usually don't. This provides mechanism to
offline/online physical CPUs.
Bug-fixes for:
* Coverity found fixes in the console and ACPI processor driver.
* PVonHVM kexec fixes along with some cleanups.
* Pages that fall within E820 gaps and non-RAM regions (and had been
released to hypervisor) would be populated back, but potentially in
non-RAM regions."
* tag 'stable/for-linus-3.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: populate correct number of pages when across mem boundary (v2)
xen PVonHVM: move shared_info to MMIO before kexec
xen: simplify init_hvm_pv_info
xen: remove cast from HYPERVISOR_shared_info assignment
xen: enable platform-pci only in a Xen guest
xen/pv-on-hvm kexec: shutdown watches from old kernel
xen/x86: avoid updating TLS descriptors if they haven't changed
xen/x86: add desc_equal() to compare GDT descriptors
xen/mm: zero PTEs for non-present MFNs in the initial page table
xen/mm: do direct hypercall in xen_set_pte() if batching is unavailable
xen/hvc: Fix up checks when the info is allocated.
xen/acpi: Fix potential memory leak.
xen/mce: add .poll method for mcelog device driver
xen/mce: schedule a workqueue to avoid sleep in atomic context
xen/pcpu: Xen physical cpus online/offline sys interface
xen/mce: Register native mce handler as vMCE bounce back point
x86, MCE, AMD: Adjust initcall sequence for xen
xen/mce: Add mcelog support for Xen platform
Currently kexec in a PVonHVM guest fails with a triple fault because the
new kernel overwrites the shared info page. The exact failure depends on
the size of the kernel image. This patch moves the pfn from RAM into
MMIO space before the kexec boot.
The pfn containing the shared_info is located somewhere in RAM. This
will cause trouble if the current kernel is doing a kexec boot into a
new kernel. The new kernel (and its startup code) can not know where the
pfn is, so it can not reserve the page. The hypervisor will continue to
update the pfn, and as a result memory corruption occours in the new
kernel.
One way to work around this issue is to allocate a page in the
xen-platform pci device's BAR memory range. But pci init is done very
late and the shared_info page is already in use very early to read the
pvclock. So moving the pfn from RAM to MMIO is racy because some code
paths on other vcpus could access the pfn during the small window when
the old pfn is moved to the new pfn. There is even a small window were
the old pfn is not backed by a mfn, and during that time all reads
return -1.
Because it is not known upfront where the MMIO region is located it can
not be used right from the start in xen_hvm_init_shared_info.
To minimise trouble the move of the pfn is done shortly before kexec.
This does not eliminate the race because all vcpus are still online when
the syscore_ops will be called. But hopefully there is no work pending
at this point in time. Also the syscore_op is run last which reduces the
risk further.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
init_hvm_pv_info is called only in PVonHVM context, move it into ifdef.
init_hvm_pv_info does not fail, make it a void function.
remove arguments from init_hvm_pv_info because they are not used by the
caller.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Both have type struct shared_info so no cast is needed.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When switching tasks in a Xen PV guest, avoid updating the TLS
descriptors if they haven't changed. This improves the speed of
context switches by almost 10% as much of the time the descriptors are
the same or only one is different.
The descriptors written into the GDT by Xen are modified from the
values passed in the update_descriptor hypercall so we keep shadow
copies of the three TLS descriptors to compare against.
lmbench3 test Before After Improvement
--------------------------------------------
lat_ctx -s 32 24 7.19 6.52 9%
lat_pipe 12.56 11.66 7%
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When constructing the initial page tables, if the MFN for a usable PFN
is missing in the p2m then that frame is initially ballooned out. In
this case, zero the PTE (as in decrease_reservation() in
drivers/xen/balloon.c).
This is obviously safe instead of having an valid PTE with an MFN of
INVALID_P2M_ENTRY (~0).
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
In xen_set_pte() if batching is unavailable (because the caller is in
an interrupt context such as handling a page fault) it would fall back
to using native_set_pte() and trapping and emulating the PTE write.
On 32-bit guests this requires two traps for each PTE write (one for
each dword of the PTE). Instead, do one mmu_update hypercall
directly.
During construction of the initial page tables, continue to use
native_set_pte() because most of the PTEs being set are in writable
and unpinned pages (see phys_pmd_init() in arch/x86/mm/init_64.c) and
using a hypercall for this is very expensive.
This significantly improves page fault performance in 32-bit PV
guests.
lmbench3 test Before After Improvement
----------------------------------------------
lat_pagefault 3.18 us 2.32 us 27%
lat_proc fork 356 us 313.3 us 11%
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When Xen hypervisor inject vMCE to guest, use native mce handler
to handle it
Signed-off-by: Ke, Liping <liping.ke@intel.com>
Signed-off-by: Jiang, Yunhong <yunhong.jiang@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When MCA error occurs, it would be handled by Xen hypervisor first,
and then the error information would be sent to initial domain for logging.
This patch gets error information from Xen hypervisor and convert
Xen format error into Linux format mcelog. This logic is basically
self-contained, not touching other kernel components.
By using tools like mcelog tool users could read specific error information,
like what they did under native Linux.
To test follow directions outlined in Documentation/acpi/apei/einj.txt
Acked-and-tested-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Ke, Liping <liping.ke@intel.com>
Signed-off-by: Jiang, Yunhong <yunhong.jiang@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
x86 has no flush_tlb_range support in instruction level. Currently the
flush_tlb_range just implemented by flushing all page table. That is not
the best solution for all scenarios. In fact, if we just use 'invlpg' to
flush few lines from TLB, we can get the performance gain from later
remain TLB lines accessing.
But the 'invlpg' instruction costs much of time. Its execution time can
compete with cr3 rewriting, and even a bit more on SNB CPU.
So, on a 512 4KB TLB entries CPU, the balance points is at:
(512 - X) * 100ns(assumed TLB refill cost) =
X(TLB flush entries) * 100ns(assumed invlpg cost)
Here, X is 256, that is 1/2 of 512 entries.
But with the mysterious CPU pre-fetcher and page miss handler Unit, the
assumed TLB refill cost is far lower then 100ns in sequential access. And
2 HT siblings in one core makes the memory access more faster if they are
accessing the same memory. So, in the patch, I just do the change when
the target entries is less than 1/16 of whole active tlb entries.
Actually, I have no data support for the percentage '1/16', so any
suggestions are welcomed.
As to hugetlb, guess due to smaller page table, and smaller active TLB
entries, I didn't see benefit via my benchmark, so no optimizing now.
My micro benchmark show in ideal scenarios, the performance improves 70
percent in reading. And in worst scenario, the reading/writing
performance is similar with unpatched 3.4-rc4 kernel.
Here is the reading data on my 2P * 4cores *HT NHM EP machine, with THP
'always':
multi thread testing, '-t' paramter is thread number:
with patch unpatched 3.4-rc4
./mprotect -t 1 14ns 24ns
./mprotect -t 2 13ns 22ns
./mprotect -t 4 12ns 19ns
./mprotect -t 8 14ns 16ns
./mprotect -t 16 28ns 26ns
./mprotect -t 32 54ns 51ns
./mprotect -t 128 200ns 199ns
Single process with sequencial flushing and memory accessing:
with patch unpatched 3.4-rc4
./mprotect 7ns 11ns
./mprotect -p 4096 -l 8 -n 10240
21ns 21ns
[ hpa: http://lkml.kernel.org/r/1B4B44D9196EFF41AE41FDA404FC0A100BFF94@SHSMSX101.ccr.corp.intel.com
has additional performance numbers. ]
Signed-off-by: Alex Shi <alex.shi@intel.com>
Link: http://lkml.kernel.org/r/1340845344-27557-3-git-send-email-alex.shi@intel.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
- When booting as PVHVM we would try to use PV console - but would not validate
the parameters causing us to crash during restore b/c we re-use the wrong event
channel.
- When booting on machines with SR-IOV PCI bridge we didn't check for the bridge
and tried to use it.
- Under AMD machines would advertise the APERFMPERF resulting in needless amount
of MSRs from the guest.
- A global value (xen_released_pages) was not subtracted at bootup when pages
were added back in. This resulted in the balloon worker having the wrong
account of how many pages were truly released.
- Fix dead-lock when xen-blkfront is run in the same domain as xen-blkback.
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Merge tag 'stable/for-linus-3.5-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull five Xen bug-fixes from Konrad Rzeszutek Wilk:
- When booting as PVHVM we would try to use PV console - but would not validate
the parameters causing us to crash during restore b/c we re-use the wrong event
channel.
- When booting on machines with SR-IOV PCI bridge we didn't check for the bridge
and tried to use it.
- Under AMD machines would advertise the APERFMPERF resulting in needless amount
of MSRs from the guest.
- A global value (xen_released_pages) was not subtracted at bootup when pages
were added back in. This resulted in the balloon worker having the wrong
account of how many pages were truly released.
- Fix dead-lock when xen-blkfront is run in the same domain as xen-blkback.
* tag 'stable/for-linus-3.5-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: mark local pages as FOREIGN in the m2p_override
xen/setup: filter APERFMPERF cpuid feature out
xen/balloon: Subtract from xen_released_pages the count that is populated.
xen/pci: Check for PCI bridge before using it.
xen/events: Add WARN_ON when quick lookup found invalid type.
xen/hvc: Check HVM_PARAM_CONSOLE_[EVTCHN|PFN] for correctness.
xen/hvc: Fix error cases around HVM_PARAM_CONSOLE_PFN
xen/hvc: Collapse error logic.
When the frontend and the backend reside on the same domain, even if we
add pages to the m2p_override, these pages will never be returned by
mfn_to_pfn because the check "get_phys_to_machine(pfn) != mfn" will
always fail, so the pfn of the frontend will be returned instead
(resulting in a deadlock because the frontend pages are already locked).
INFO: task qemu-system-i38:1085 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
qemu-system-i38 D ffff8800cfc137c0 0 1085 1 0x00000000
ffff8800c47ed898 0000000000000282 ffff8800be4596b0 00000000000137c0
ffff8800c47edfd8 ffff8800c47ec010 00000000000137c0 00000000000137c0
ffff8800c47edfd8 00000000000137c0 ffffffff82213020 ffff8800be4596b0
Call Trace:
[<ffffffff81101ee0>] ? __lock_page+0x70/0x70
[<ffffffff81a0fdd9>] schedule+0x29/0x70
[<ffffffff81a0fe80>] io_schedule+0x60/0x80
[<ffffffff81101eee>] sleep_on_page+0xe/0x20
[<ffffffff81a0e1ca>] __wait_on_bit_lock+0x5a/0xc0
[<ffffffff81101ed7>] __lock_page+0x67/0x70
[<ffffffff8106f750>] ? autoremove_wake_function+0x40/0x40
[<ffffffff811867e6>] ? bio_add_page+0x36/0x40
[<ffffffff8110b692>] set_page_dirty_lock+0x52/0x60
[<ffffffff81186021>] bio_set_pages_dirty+0x51/0x70
[<ffffffff8118c6b4>] do_blockdev_direct_IO+0xb24/0xeb0
[<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00
[<ffffffff8118ca95>] __blockdev_direct_IO+0x55/0x60
[<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00
[<ffffffff811e91c8>] ext3_direct_IO+0xf8/0x390
[<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00
[<ffffffff81004b60>] ? xen_mc_flush+0xb0/0x1b0
[<ffffffff81104027>] generic_file_aio_read+0x737/0x780
[<ffffffff813bedeb>] ? gnttab_map_refs+0x15b/0x1e0
[<ffffffff811038f0>] ? find_get_pages+0x150/0x150
[<ffffffff8119736c>] aio_rw_vect_retry+0x7c/0x1d0
[<ffffffff811972f0>] ? lookup_ioctx+0x90/0x90
[<ffffffff81198856>] aio_run_iocb+0x66/0x1a0
[<ffffffff811998b8>] do_io_submit+0x708/0xb90
[<ffffffff81199d50>] sys_io_submit+0x10/0x20
[<ffffffff81a18d69>] system_call_fastpath+0x16/0x1b
The explanation is in the comment within the code:
We need to do this because the pages shared by the frontend
(xen-blkfront) can be already locked (lock_page, called by
do_read_cache_page); when the userspace backend tries to use them
with direct_IO, mfn_to_pfn returns the pfn of the frontend, so
do_blockdev_direct_IO is going to try to lock the same pages
again resulting in a deadlock.
A simplified call graph looks like this:
pygrub QEMU
-----------------------------------------------
do_read_cache_page io_submit
| |
lock_page ext3_direct_IO
|
bio_add_page
|
lock_page
Internally the xen-blkback uses m2p_add_override to swizzle (temporarily)
a 'struct page' to have a different MFN (so that it can point to another
guest). It also can easily find out whether another pfn corresponding
to the mfn exists in the m2p, and can set the FOREIGN bit
in the p2m, making sure that mfn_to_pfn returns the pfn of the backend.
This allows the backend to perform direct_IO on these pages, but as a
side effect prevents the frontend from using get_user_pages_fast on
them while they are being shared with the backend.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
There were paravirt_ops hooks for the full register set variant of
{rd,wr}msr_safe which are actually not used by anyone anymore. Remove
them to make the code cleaner and avoid silent breakages when the pvops
members were uninitialized. This has been boot-tested natively and under
Xen with PVOPS enabled and disabled on one machine.
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Link: http://lkml.kernel.org/r/1338562358-28182-2-git-send-email-bp@amd64.org
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
ipi_call_lock/unlock() lock resp. unlock call_function.lock. This lock
protects only the call_function data structure itself, but it's
completely unrelated to cpu_online_mask. The mask to which the IPIs
are sent is calculated before call_function.lock is taken in
smp_call_function_many(), so the locking around set_cpu_online() is
pointless and can be removed.
[ tglx: Massaged changelog ]
Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Cc: ralf@linux-mips.org
Cc: sshtylyov@mvista.com
Cc: david.daney@cavium.com
Cc: nikunj@linux.vnet.ibm.com
Cc: paulmck@linux.vnet.ibm.com
Cc: axboe@kernel.dk
Cc: peterz@infradead.org
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1338275765-3217-7-git-send-email-yong.zhang0@gmail.com
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Xen PV kernels allow access to the APERF/MPERF registers to read the
effective frequency. Access to the MSRs is however redirected to the
currently scheduled physical CPU, making consecutive read and
compares unreliable. In addition each rdmsr traps into the hypervisor.
So to avoid bogus readouts and expensive traps, disable the kernel
internal feature flag for APERF/MPERF if running under Xen.
This will
a) remove the aperfmperf flag from /proc/cpuinfo
b) not mislead the power scheduler (arch/x86/kernel/cpu/sched.c) to
use the feature to improve scheduling (by default disabled)
c) not mislead the cpufreq driver to use the MSRs
This does not cover userland programs which access the MSRs via the
device file interface, but this will be addressed separately.
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Cc: stable@vger.kernel.org # v3.0+
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Stub out MSR methods that aren't actually needed. This fixes a crash
as Xen Dom0 on AMD Trinity systems. A bigger patch should be added to
remove the paravirt machinery completely for the methods which
apparently have no users!
Reported-by: Andre Przywara <andre.przywara@amd.com>
Link: http://lkml.kernel.org/r/20120530222356.GA28417@andromeda.dapyr.net
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@vger.kernel.org>
We did not take into account that xen_released_pages would be
used outside the initial E820 parsing code. As such we would
did not subtract from xen_released_pages the count of pages
that we had populated back (instead we just did a simple
extra_pages = released - populated).
The balloon driver uses xen_released_pages to set the initial
current_pages count. If this is wrong (too low) then when a new
(higher) target is set, the balloon driver will request too many pages
from Xen."
This fixes errors such as:
(XEN) memory.c:133:d0 Could not allocate order=0 extent: id=0 memflags=0 (51 of 512)
during bootup and
free_memory : 0
where the free_memory should be 128.
Acked-by: David Vrabel <david.vrabel@citrix.com>
[v1: Per David's review made the git commit better]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* Extend the APIC ops implementation and add IRQ_WORKER vector support so that 'perf' can work properly.
* Fix self-ballooning code, and balloon logic when booting as initial domain.
* Move array printing code to generic debugfs
* Support XenBus domains.
* Lazily free grants when a domain is dead/non-existent.
* In M2P code use batching calls
Bug-fixes:
* Fix NULL dereference in allocation failure path (hvc_xen)
* Fix unbinding of IRQ_WORKER vector during vCPU hot-unplug
* Fix HVM guest resume - we would leak an PIRQ value instead of reusing the existing one.
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Merge tag 'stable/for-linus-3.5-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull Xen updates from Konrad Rzeszutek Wilk:
"Features:
* Extend the APIC ops implementation and add IRQ_WORKER vector
support so that 'perf' can work properly.
* Fix self-ballooning code, and balloon logic when booting as initial
domain.
* Move array printing code to generic debugfs
* Support XenBus domains.
* Lazily free grants when a domain is dead/non-existent.
* In M2P code use batching calls
Bug-fixes:
* Fix NULL dereference in allocation failure path (hvc_xen)
* Fix unbinding of IRQ_WORKER vector during vCPU hot-unplug
* Fix HVM guest resume - we would leak an PIRQ value instead of
reusing the existing one."
Fix up add-add onflicts in arch/x86/xen/enlighten.c due to addition of
apic ipi interface next to the new apic_id functions.
* tag 'stable/for-linus-3.5-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: do not map the same GSI twice in PVHVM guests.
hvc_xen: NULL dereference on allocation failure
xen: Add selfballoning memory reservation tunable.
xenbus: Add support for xenbus backend in stub domain
xen/smp: unbind irqworkX when unplugging vCPUs.
xen: enter/exit lazy_mmu_mode around m2p_override calls
xen/acpi/sleep: Enable ACPI sleep via the __acpi_os_prepare_sleep
xen: implement IRQ_WORK_VECTOR handler
xen: implement apic ipi interface
xen/setup: update VA mapping when releasing memory during setup
xen/setup: Combine the two hypercall functions - since they are quite similar.
xen/setup: Populate freed MFNs from non-RAM E820 entries and gaps to E820 RAM
xen/setup: Only print "Freeing XXX-YYY pfn range: Z pages freed" if Z > 0
xen/gnttab: add deferred freeing logic
debugfs: Add support to print u32 array in debugfs
xen/p2m: An early bootup variant of set_phys_to_machine
xen/p2m: Collapse early_alloc_p2m_middle redundant checks.
xen/p2m: Allow alloc_p2m_middle to call reserve_brk depending on argument
xen/p2m: Move code around to allow for better re-usage.
Pull exception table generation updates from Ingo Molnar:
"The biggest change here is to allow the build-time sorting of the
exception table, to speed up booting. This is achieved by the
architecture enabling BUILDTIME_EXTABLE_SORT. This option is enabled
for x86 and MIPS currently.
On x86 a number of fixes and changes were needed to allow build-time
sorting of the exception table, in particular a relocation invariant
exception table format was needed. This required the abstracting out
of exception table protocol and the removal of 20 years of accumulated
assumptions about the x86 exception table format.
While at it, this tree also cleans up various other aspects of
exception handling, such as early(er) exception handling for
rdmsr_safe() et al.
All in one, as the result of these changes the x86 exception code is
now pretty nice and modern. As an added bonus any regressions in this
code will be early and violent crashes, so if you see any of those,
you'll know whom to blame!"
Fix up trivial conflicts in arch/{mips,x86}/Kconfig files due to nearby
modifications of other core architecture options.
* 'x86-extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits)
Revert "x86, extable: Disable presorted exception table for now"
scripts/sortextable: Handle relative entries, and other cleanups
x86, extable: Switch to relative exception table entries
x86, extable: Disable presorted exception table for now
x86, extable: Add _ASM_EXTABLE_EX() macro
x86, extable: Remove open-coded exception table entries in arch/x86/ia32/ia32entry.S
x86, extable: Remove open-coded exception table entries in arch/x86/include/asm/xsave.h
x86, extable: Remove open-coded exception table entries in arch/x86/include/asm/kvm_host.h
x86, extable: Remove the now-unused __ASM_EX_SEC macros
x86, extable: Remove open-coded exception table entries in arch/x86/xen/xen-asm_32.S
x86, extable: Remove open-coded exception table entries in arch/x86/um/checksum_32.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/usercopy_32.c
x86, extable: Remove open-coded exception table entries in arch/x86/lib/putuser.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/getuser.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/csum-copy_64.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_nocache_64.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/checksum_32.S
x86, extable: Remove open-coded exception table entries in arch/x86/kernel/test_rodata.c
x86, extable: Remove open-coded exception table entries in arch/x86/kernel/entry_64.S
...
Pull x86/apic changes from Ingo Molnar:
"Most of the changes are about helping virtualized guest kernels
achieve better performance."
Fix up trivial conflicts with the iommu updates to arch/x86/kernel/apic/io_apic.c
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic: Implement EIO micro-optimization
x86/apic: Add apic->eoi_write() callback
x86/apic: Use symbolic APIC_EOI_ACK
x86/apic: Fix typo EIO_ACK -> EOI_ACK and document it
x86/xen/apic: Add missing #include <xen/xen.h>
x86/apic: Only compile local function if used with !CONFIG_GENERIC_PENDING_IRQ
x86/apic: Fix UP boot crash
x86: Conditionally update time when ack-ing pending irqs
xen/apic: implement io apic read with hypercall
Revert "xen/x86: Workaround 'x86/ioapic: Add register level checks to detect bogus io-apic entries'"
xen/x86: Implement x86_apic_ops
x86/apic: Replace io_apic_ops with x86_io_apic_ops.
Pull smp hotplug cleanups from Thomas Gleixner:
"This series is merily a cleanup of code copied around in arch/* and
not changing any of the real cpu hotplug horrors yet. I wish I'd had
something more substantial for 3.5, but I underestimated the lurking
horror..."
Fix up trivial conflicts in arch/{arm,sparc,x86}/Kconfig and
arch/sparc/include/asm/thread_info_32.h
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (79 commits)
um: Remove leftover declaration of alloc_task_struct_node()
task_allocator: Use config switches instead of magic defines
sparc: Use common threadinfo allocator
score: Use common threadinfo allocator
sh-use-common-threadinfo-allocator
mn10300: Use common threadinfo allocator
powerpc: Use common threadinfo allocator
mips: Use common threadinfo allocator
hexagon: Use common threadinfo allocator
m32r: Use common threadinfo allocator
frv: Use common threadinfo allocator
cris: Use common threadinfo allocator
x86: Use common threadinfo allocator
c6x: Use common threadinfo allocator
fork: Provide kmemcache based thread_info allocator
tile: Use common threadinfo allocator
fork: Provide weak arch_release_[task_struct|thread_info] functions
fork: Move thread info gfp flags to header
fork: Remove the weak insanity
sh: Remove cpu_idle_wait()
...
This file depends on <xen/xen.h>, but the dependency was hidden due
to: <asm/acpi.h> -> <asm/trampoline.h> -> <asm/io.h> -> <xen/xen.h>
With the removal of <asm/trampoline.h>, this exposed the missing
Cc: Len Brown <lenb@kernel.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/n/tip-7ccybvue6mw6wje3uxzzcglj@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
* stable/autoballoon.v5.2:
xen/setup: update VA mapping when releasing memory during setup
xen/setup: Combine the two hypercall functions - since they are quite similar.
xen/setup: Populate freed MFNs from non-RAM E820 entries and gaps to E820 RAM
xen/setup: Only print "Freeing XXX-YYY pfn range: Z pages freed" if Z > 0
xen/p2m: An early bootup variant of set_phys_to_machine
xen/p2m: Collapse early_alloc_p2m_middle redundant checks.
xen/p2m: Allow alloc_p2m_middle to call reserve_brk depending on argument
xen/p2m: Move code around to allow for better re-usage.
Provide the registration callback to call in the Xen's
ACPI sleep functionality. This means that during S3/S5
we make a hypercall XENPF_enter_acpi_sleep with the
proper PM1A/PM1B registers.
Based of Ke Yu's <ke.yu@intel.com> initial idea.
[ From http://xenbits.xensource.com/linux-2.6.18-xen.hg
change c68699484a65 ]
[v1: Added Copyright and license]
[v2: Added check if PM1A/B the 16-bits MSB contain something. The spec
only uses 16-bits but might have more in future]
Signed-off-by: Liang Tang <liang.tang@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Map native ipi vector to xen vector.
Implement apic ipi interface with xen_send_IPI_one.
Tested-by: Steven Noonan <steven@uplinklabs.net>
Signed-off-by: Ben Guthro <ben@guthro.net>
Signed-off-by: Lin Ming <mlin@ss.pku.edu.cn>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
In xen_memory_setup(), if a page that is being released has a VA
mapping this must also be updated. Otherwise, the page will be not
released completely -- it will still be referenced in Xen and won't be
freed util the mapping is removed and this prevents it from being
reallocated at a different PFN.
This was already being done for the ISA memory region in
xen_ident_map_ISA() but on many systems this was omitting a few pages
as many systems marked a few pages below the ISA memory region as
reserved in the e820 map.
This fixes errors such as:
(XEN) page_alloc.c:1148:d0 Over-allocation for domain 0: 2097153 > 2097152
(XEN) memory.c:133:d0 Could not allocate order=0 extent: id=0 memflags=0 (0 of 17)
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
They use the same set of arguments, so it is just the matter
of using the proper hypercall.
Acked-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When the Xen hypervisor boots a PV kernel it hands it two pieces
of information: nr_pages and a made up E820 entry.
The nr_pages value defines the range from zero to nr_pages of PFNs
which have a valid Machine Frame Number (MFN) underneath it. The
E820 mirrors that (with the VGA hole):
BIOS-provided physical RAM map:
Xen: 0000000000000000 - 00000000000a0000 (usable)
Xen: 00000000000a0000 - 0000000000100000 (reserved)
Xen: 0000000000100000 - 0000000080800000 (usable)
The fun comes when a PV guest that is run with a machine E820 - that
can either be the initial domain or a PCI PV guest, where the E820
looks like the normal thing:
BIOS-provided physical RAM map:
Xen: 0000000000000000 - 000000000009e000 (usable)
Xen: 000000000009ec00 - 0000000000100000 (reserved)
Xen: 0000000000100000 - 0000000020000000 (usable)
Xen: 0000000020000000 - 0000000020200000 (reserved)
Xen: 0000000020200000 - 0000000040000000 (usable)
Xen: 0000000040000000 - 0000000040200000 (reserved)
Xen: 0000000040200000 - 00000000bad80000 (usable)
Xen: 00000000bad80000 - 00000000badc9000 (ACPI NVS)
..
With that overlaying the nr_pages directly on the E820 does not
work as there are gaps and non-RAM regions that won't be used
by the memory allocator. The 'xen_release_chunk' helps with that
by punching holes in the P2M (PFN to MFN lookup tree) for those
regions and tells us that:
Freeing 20000-20200 pfn range: 512 pages freed
Freeing 40000-40200 pfn range: 512 pages freed
Freeing bad80-badf4 pfn range: 116 pages freed
Freeing badf6-bae7f pfn range: 137 pages freed
Freeing bb000-100000 pfn range: 282624 pages freed
Released 283999 pages of unused memory
Those 283999 pages are subtracted from the nr_pages and are returned
to the hypervisor. The end result is that the initial domain
boots with 1GB less memory as the nr_pages has been subtracted by
the amount of pages residing within the PCI hole. It can balloon up
to that if desired using 'xl mem-set 0 8092', but the balloon driver
is not always compiled in for the initial domain.
This patch, implements the populate hypercall (XENMEM_populate_physmap)
which increases the the domain with the same amount of pages that
were released.
The other solution (that did not work) was to transplant the MFN in
the P2M tree - the ones that were going to be freed were put in
the E820_RAM regions past the nr_pages. But the modifications to the
M2P array (the other side of creating PTEs) were not carried away.
As the hypervisor is the only one capable of modifying that and the
only two hypercalls that would do this are: the update_va_mapping
(which won't work, as during initial bootup only PFNs up to nr_pages
are mapped in the guest) or via the populate hypercall.
The end result is that the kernel can now boot with the
nr_pages without having to subtract the 283999 pages.
On a 8GB machine, with various dom0_mem= parameters this is what we get:
no dom0_mem
-Memory: 6485264k/9435136k available (5817k kernel code, 1136060k absent, 1813812k reserved, 2899k data, 696k init)
+Memory: 7619036k/9435136k available (5817k kernel code, 1136060k absent, 680040k reserved, 2899k data, 696k init)
dom0_mem=3G
-Memory: 2616536k/9435136k available (5817k kernel code, 1136060k absent, 5682540k reserved, 2899k data, 696k init)
+Memory: 2703776k/9435136k available (5817k kernel code, 1136060k absent, 5595300k reserved, 2899k data, 696k init)
dom0_mem=max:3G
-Memory: 2696732k/4281724k available (5817k kernel code, 1136060k absent, 448932k reserved, 2899k data, 696k init)
+Memory: 2702204k/4281724k available (5817k kernel code, 1136060k absent, 443460k reserved, 2899k data, 696k init)
And the 'xm list' or 'xl list' now reflect what the dom0_mem=
argument is.
Acked-by: David Vrabel <david.vrabel@citrix.com>
[v2: Use populate hypercall]
[v3: Remove debug printks]
[v4: Simplify code]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Otherwise we can get these meaningless:
Freeing bad80-badf4 pfn range: 0 pages freed
We also can do this for the summary ones - no point of printing
"Set 0 page(s) to 1-1 mapping"
Acked-by: David Vrabel <david.vrabel@citrix.com>
[v1: Extended to the summary printks]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The accessing PCI configuration space with the PCI BIOS32 service does
not work in PV guests.
On systems without MMCONFIG or where the BIOS hasn't marked the
MMCONFIG region as reserved in the e820 map, the BIOS service is
probed (even though direct access is preferred) and this hangs.
CC: stable@kernel.org
Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
[v1: Fixed compile error when CONFIG_PCI is not set]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If I try to do "cat /sys/kernel/debug/kernel_page_tables"
I end up with:
BUG: unable to handle kernel paging request at ffffc7fffffff000
IP: [<ffffffff8106aa51>] ptdump_show+0x221/0x480
PGD 0
Oops: 0000 [#1] SMP
CPU 0
.. snip..
RAX: 0000000000000000 RBX: ffffc00000000fff RCX: 0000000000000000
RDX: 0000800000000000 RSI: 0000000000000000 RDI: ffffc7fffffff000
which is due to the fact we are trying to access a PFN that is not
accessible to us. The reason (at least in this case) was that
PGD[256] is set to __HYPERVISOR_VIRT_START which was setup (by the
hypervisor) to point to a read-only linear map of the MFN->PFN array.
During our parsing we would get the MFN (a valid one), try to look
it up in the MFN->PFN tree and find it invalid and return ~0 as PFN.
Then pte_mfn_to_pfn would happilly feed that in, attach the flags
and return it back to the caller. 'ptdump_show' bitshifts it and
gets and invalid value that it tries to dereference.
Instead of doing all of that, we detect the ~0 case and just
return !_PAGE_PRESENT.
This bug has been in existence .. at least until 2.6.37 (yikes!)
CC: stable@kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
On x86_64 on AMD machines where the first APIC_ID is not zero, we get:
ACPI: LAPIC (acpi_id[0x01] lapic_id[0x10] enabled)
BIOS bug: APIC version is 0 for CPU 1/0x10, fixing up to 0x10
BIOS bug: APIC version mismatch, boot CPU: 0, CPU 1: version 10
which means that when the ACPI processor driver loads and
tries to parse the _Pxx states it fails to do as, as it
ends up calling acpi_get_cpuid which does this:
for_each_possible_cpu(i) {
if (cpu_physical_id(i) == apic_id)
return i;
}
And the bootup CPU, has not been found so it fails and returns -1
for the first CPU - which then subsequently in the loop that
"acpi_processor_get_info" does results in returning an error, which
means that "acpi_processor_add" failing and per_cpu(processor)
is never set (and is NULL).
That means that when xen-acpi-processor tries to load (much much
later on) and parse the P-states it gets -ENODEV from
acpi_processor_register_performance() (which tries to read
the per_cpu(processor)) and fails to parse the data.
Reported-by-and-Tested-by: Stefan Bader <stefan.bader@canonical.com>
Suggested-by: Boris Ostrovsky <boris.ostrovsky@amd.com>
[v2: Bit-shift APIC ID by 24 bits]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Implements xen_io_apic_read with hypercall, so it returns proper
IO-APIC information instead of fabricated one.
Fallback to return an emulated IO_APIC values if hypercall fails.
[v2: fallback to return an emulated IO_APIC values if hypercall fails]
Signed-off-by: Lin Ming <mlin@ss.pku.edu.cn>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This reverts commit 2531d64b6f.
The two patches:
x86/apic: Replace io_apic_ops with x86_io_apic_ops.
xen/x86: Implement x86_apic_ops
take care of fixing it properly.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Or rather just implement one different function as opposed
to the native one : the read function.
We synthesize the values.
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
[v1: Rebased on top of tip/x86/urgent]
[v2: Return 0xfd instead of 0xff in the default case]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
In xen_restore_fl_direct(), xen_force_evtchn_callback() was being
called even if no events were pending. This resulted in (depending on
workload) about a 100 times as many xen_version hypercalls as
necessary.
Fix this by correcting the sense of the conditional jump.
This seems to give a significant performance benefit for some
workloads.
There is some subtle tricksy "..since the check here is trying to
check both pending and masked in a single cmpw, but I think this is
correct. It will call check_events now only when the combined
mask+pending word is 0x0001 (aka unmasked, pending)." (Ian)
CC: stable@kernel.org
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When we boot on a machine that can hotplug CPUs and we
are using 'dom0_max_vcpus=X' on the Xen hypervisor line
to clip the amount of CPUs available to the initial domain,
we get this:
(XEN) Command line: com1=115200,8n1 dom0_mem=8G noreboot dom0_max_vcpus=8 sync_console mce_verbosity=verbose console=com1,vga loglvl=all guest_loglvl=all
.. snip..
DMI: Intel Corporation S2600CP/S2600CP, BIOS SE5C600.86B.99.99.x032.072520111118 07/25/2011
.. snip.
SMP: Allowing 64 CPUs, 32 hotplug CPUs
installing Xen timer for CPU 7
cpu 7 spinlock event irq 361
NMI watchdog: disabled (cpu7): hardware events not enabled
Brought up 8 CPUs
.. snip..
[acpi processor finds the CPUs are not initialized and starts calling
arch_register_cpu, which creates /sys/devices/system/cpu/cpu8/online]
CPU 8 got hotplugged
CPU 9 got hotplugged
CPU 10 got hotplugged
.. snip..
initcall 1_acpi_battery_init_async+0x0/0x1b returned 0 after 406 usecs
calling erst_init+0x0/0x2bb @ 1
[and the scheduler sticks newly started tasks on the new CPUs, but
said CPUs cannot be initialized b/c the hypervisor has limited the
amount of vCPUS to 8 - as per the dom0_max_vcpus=8 flag.
The spinlock tries to kick the other CPU, but the structure for that
is not initialized and we crash.]
BUG: unable to handle kernel paging request at fffffffffffffed8
IP: [<ffffffff81035289>] xen_spin_lock+0x29/0x60
PGD 180d067 PUD 180e067 PMD 0
Oops: 0002 [#1] SMP
CPU 7
Modules linked in:
Pid: 1, comm: swapper/0 Not tainted 3.4.0-rc2upstream-00001-gf5154e8 #1 Intel Corporation S2600CP/S2600CP
RIP: e030:[<ffffffff81035289>] [<ffffffff81035289>] xen_spin_lock+0x29/0x60
RSP: e02b:ffff8801fb9b3a70 EFLAGS: 00010282
With this patch, we cap the amount of vCPUS that the initial domain
can run, to exactly what dom0_max_vcpus=X has specified.
In the future, if there is a hypercall that will allow a running
domain to expand past its initial set of vCPUS, this patch should
be re-evaluated.
CC: stable@kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
There are exactly four users of __monitor and __mwait:
- cstate.c (which allows acpi_processor_ffh_cstate_enter to be called
when the cpuidle API drivers are used. However patch
"cpuidle: replace xen access to x86 pm_idle and default_idle"
provides a mechanism to disable the cpuidle and use safe_halt.
- smpboot (which allows mwait_play_dead to be called). However
safe_halt is always used so we skip that.
- intel_idle (same deal as above).
- acpi_pad.c. This the one that we do not want to run as we
will hit the below crash.
Why do we want to expose MWAIT_LEAF in the first place?
We want it for the xen-acpi-processor driver - which uploads
C-states to the hypervisor. If MWAIT_LEAF is set, the cstate.c
sets the proper address in the C-states so that the hypervisor
can benefit from using the MWAIT functionality. And that is
the sole reason for using it.
Without this patch, if a module performs mwait or monitor we
get this:
invalid opcode: 0000 [#1] SMP
CPU 2
.. snip..
Pid: 5036, comm: insmod Tainted: G O 3.4.0-rc2upstream-dirty #2 Intel Corporation S2600CP/S2600CP
RIP: e030:[<ffffffffa000a017>] [<ffffffffa000a017>] mwait_check_init+0x17/0x1000 [mwait_check]
RSP: e02b:ffff8801c298bf18 EFLAGS: 00010282
RAX: ffff8801c298a010 RBX: ffffffffa03b2000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8801c29800d8 RDI: ffff8801ff097200
RBP: ffff8801c298bf18 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: ffffffffa000a000 R14: 0000005148db7294 R15: 0000000000000003
FS: 00007fbb364f2700(0000) GS:ffff8801ff08c000(0000) knlGS:0000000000000000
CS: e033 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 000000000179f038 CR3: 00000001c9469000 CR4: 0000000000002660
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process insmod (pid: 5036, threadinfo ffff8801c298a000, task ffff8801c29cd7e0)
Stack:
ffff8801c298bf48 ffffffff81002124 ffffffffa03b2000 00000000000081fd
000000000178f010 000000000178f030 ffff8801c298bf78 ffffffff810c41e6
00007fff3fb30db9 00007fff3fb30db9 00000000000081fd 0000000000010000
Call Trace:
[<ffffffff81002124>] do_one_initcall+0x124/0x170
[<ffffffff810c41e6>] sys_init_module+0xc6/0x220
[<ffffffff815b15b9>] system_call_fastpath+0x16/0x1b
Code: <0f> 01 c8 31 c0 0f 01 c9 c9 c3 00 00 00 00 00 00 00 00 00 00 00 00
RIP [<ffffffffa000a017>] mwait_check_init+0x17/0x1000 [mwait_check]
RSP <ffff8801c298bf18>
---[ end trace 16582fc8a3d1e29a ]---
Kernel panic - not syncing: Fatal exception
With this module (which is what acpi_pad.c would hit):
MODULE_AUTHOR("Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>");
MODULE_DESCRIPTION("mwait_check_and_back");
MODULE_LICENSE("GPL");
MODULE_VERSION();
static int __init mwait_check_init(void)
{
__monitor((void *)¤t_thread_info()->flags, 0, 0);
__mwait(0, 0);
return 0;
}
static void __exit mwait_check_exit(void)
{
}
module_init(mwait_check_init);
module_exit(mwait_check_exit);
Reported-by: Liu, Jinsong <jinsong.liu@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20120420124557.246929343@linutronix.de
Preparatory patch to use the generic idle thread allocation.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20120420124557.176604405@linutronix.de
Remove open-coded exception table entries in arch/x86/xen/xen-asm_32.S,
and replace them with _ASM_EXTABLE() macros; this will allow us to
change the format and type of the exception table entries.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com
This reverts commit b960d6c43a.
If we have another thread (very likely) touched the list, we
end up hitting a problem "that the next element is wrong because
we should be able to cope with that. The problem is that the
next->next pointer would be set LIST_POISON1. " (Stefano's
comment on the patch).
Reverting for now.
Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* commit 'c104f1fa1ecf4ee0fc06e31b1f77630b2551be81': (14566 commits)
cpufreq: OMAP: fix build errors: depends on ARCH_OMAP2PLUS
sparc64: Eliminate obsolete __handle_softirq() function
sparc64: Fix bootup crash on sun4v.
kconfig: delete last traces of __enabled_ from autoconf.h
Revert "kconfig: fix __enabled_ macros definition for invisible and un-selected symbols"
kconfig: fix IS_ENABLED to not require all options to be defined
irq_domain: fix type mismatch in debugfs output format
staging: android: fix mem leaks in __persistent_ram_init()
staging: vt6656: Don't leak memory in drivers/staging/vt6656/ioctl.c::private_ioctl()
staging: iio: hmc5843: Fix crash in probe function.
panic: fix stack dump print on direct call to panic()
drivers/rtc/rtc-pl031.c: enable clock on all ST variants
Revert "mm: vmscan: fix misused nr_reclaimed in shrink_mem_cgroup_zone()"
hugetlb: fix race condition in hugetlb_fault()
drivers/rtc/rtc-twl.c: use static register while reading time
drivers/rtc/rtc-s3c.c: add placeholder for driver private data
drivers/rtc/rtc-s3c.c: fix compilation error
MAINTAINERS: add PCDP console maintainer
memcg: do not open code accesses to res_counter members
drivers/rtc/rtc-efi.c: fix section mismatch warning
...
Use list_for_each_entry_safe and remove the spin_lock acquisition in
m2p_find_override.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Move the code from Xen to debugfs to make the code common
for other users as well.
Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com>
[v1: Fixed rebase issues]
[v2: Fixed PPC compile issues]
Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* one is a workaround that will be removed in v3.5 with proper fix in the tip/x86 tree,
* the other is to fix drivers to load on PV (a previous patch made them only
load in PVonHVM mode).
The rest are just minor fixes in the various drivers and some cleanup in the
core code.
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Merge tag 'stable/for-linus-3.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull xen fixes from Konrad Rzeszutek Wilk:
"Two fixes for regressions:
* one is a workaround that will be removed in v3.5 with proper fix in
the tip/x86 tree,
* the other is to fix drivers to load on PV (a previous patch made
them only load in PVonHVM mode).
The rest are just minor fixes in the various drivers and some cleanup
in the core code."
* tag 'stable/for-linus-3.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pcifront: avoid pci_frontend_enable_msix() falsely returning success
xen/pciback: fix XEN_PCI_OP_enable_msix result
xen/smp: Remove unnecessary call to smp_processor_id()
xen/x86: Workaround 'x86/ioapic: Add register level checks to detect bogus io-apic entries'
xen: only check xen_platform_pci_unplug if hvm
During early bootup we can't use alloc_page, so to allocate
leaf pages in the P2M we need to use extend_brk. For that
we are utilizing the early_alloc_p2m and early_alloc_p2m_middle
functions to do the job for us. This function follows the
same logic as set_phys_to_machine.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
At the start of the function we were checking for idx != 0
and bailing out. And later calling extend_brk if idx != 0.
That is unnecessary so remove that checks.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
For identity cases we want to call reserve_brk only on the boundary
conditions of the middle P2M (so P2M[x][y][0] = extend_brk). This is
to work around identify regions (PCI spaces, gaps in E820) which are not
aligned on 2MB regions.
However for the case were we want to allocate P2M middle leafs at the
early bootup stage, irregardless of this alignment check we need some
means of doing that. For that we provide the new argument.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We are going to be using the early_alloc_p2m (and
early_alloc_p2m_middle) code in follow up patches which
are not related to setting identity pages.
Hence lets move the code out in its own function and
rename them as appropiate.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
There is an extra and unnecessary call to smp_processor_id()
in cpu_bringup(). Remove it.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
