If we should happen to get an altivec assist exception while executing in
the kernel, we will currently try to handle it and fail, and end up oopsing
with (apparently) a segfault. (An altivec assist exception occurs for
floating-point altivec instructions with denormalized inputs or outputs if
the altivec unit is in java mode.)
This patch checks explicitly if we are in user mode and prints a useful
message if not.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently the procedure in the ppc32 kernel that synchronizes the timebase
registers across an SMP powermac system does so by setting both timebases
to zero. That is OK at boot but causes problems if done later. So that we
can do hotplug CPU on these machines, this patch changes the code so it
reads the timebase from one CPU and transfers the value to the other CPU.
(Hotplug CPU is needed for sleep (aka suspend to RAM) to work.)
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds interrupt acknowledge to the PPC4xx PIC enable_irq
implementation for level-sensitive IRQ sources. This helps in cases when
enable/disable_irq is used in interrupt handlers for hardware, which
requires IRQ acknowledge to be issued from non-interrupt context (e.g.
when actual ACK in device needs an I2C transaction). For such strange
hardware, interrupt handler disables IRQ and defers actual ACK to some
other context. When this happens, IRQ is enabled again. For
level-sensitive sources we get spurious triggering right after IRQ is
enabled. This patch fixes this.
Suggested by Tolunay Orkun <listmember@orkun.us>.
Signed-off-by: Eugene Surovegin <ebs@ebshome.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The code that went into arch/ppc/kernel/signal.c recently to handle process
freezing seems to contain a dubious assumption: that a process that calls
do_signal when PF_FREEZE is set will have entered the kernel because of a
system call. This patch removes that assumption.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix the access-above-bottom-of-stack crash.
1. Allows to preserve the valueable optimization
2. Works for NMIs
3. Doesn't care whether or not there are more of the like instances
where the stack is left empty.
4. Seems to work for me without the crashes:)
(akpm: this is still under discussion, although I _think_ it's OK. You might
want to hold off)
Signed-off-by: Stas Sergeev <stsp@aknet.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
)
From: Russell King <rmk+lkml@arm.linux.org.uk>
Oddly, max_low_pfn/max_pfn end up being the number of pages in the system,
rather than the maximum PFN on ARM. This doesn't seem to cause any problems,
so just add a note about it.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
)
From: Russell King <rmk+lkml@arm.linux.org.uk>
For some reason, this help text was missed when the file was last audited
by the documentation referencing folk. Fix this incorrect documentation
reference.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
)
From: Russell King <rmk+lkml@arm.linux.org.uk>
ARM wasn't raising a SIGBUS with a siginfo structure. Fix
__do_user_fault() to allow us to use it for SIGBUS conditions, and arrange
for the sigbus path to use this.
We need to prevent the siginfo code being called if we do not have a user
space context to call it, so consolidate the "user_mode()" tests.
Thanks to Ian Campbell who spotted this oversight.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
