linux/drivers
Andy Shevchenko 78a2ca2727 mmc: sdhci: check host->clock before using it as a denominator
Sometimes host->clock could be zero which is a legal situation. This
patch checks host->clock before usage as a denominator when timeout is
calculated. A similar patch is applied for mmc core (see commit e9b8684,
"mmc: fix division by zero in MMC core").

Without this patch, the execution of the sdhci_calc_timeout could end up
with a backtrace:

<0>[    4.014319] divide error: 0000 [#1] PREEMPT SMP
<4>[    4.014352] Modules linked in: g_ether
<4>[    4.014376]
<4>[    4.014393] Pid: 33, comm: kworker/u:2 Not tainted 3.0.0+ #646
<4>[    4.014421] EIP: 0060:[<c12fa38e>] EFLAGS: 00010046 CPU: 1
<4>[    4.014449] EIP is at sdhci_calc_timeout+0x2e/0x100
<4>[    4.014468] EAX: 00000000 EBX: f5930fc8 ECX: 00000000 EDX: 00000000
<4>[    4.014488] ESI: f5291de8 EDI: f5291db8 EBP: f5291c6c ESP: f5291c50
<4>[    4.014508]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
<0>[    4.014529] Process kworker/u:2 (pid: 33, ti=f5290000 task=f53065a0 task.ti=f5290000)
<0>[    4.014546] Stack:
<4>[    4.014557]  00000082 c1054fdd f5291c78 04000000 f5930fc8 f5291de8 f5291db8 f5291cac
<4>[    4.014611]  c12fab7c c107a98b f5291c88 c13b6d3f f593109c f5882000 f5291cac c1054fdd
<4>[    4.014663]  00000000 00000000 f5882000 00000082 f5930fc8 f5291db8 0000000a f5291ccc
<0>[    4.014716] Call Trace:
<4>[    4.014743]  [<c1054fdd>] ? mod_timer+0x11d/0x380
<4>[    4.014770]  [<c12fab7c>] sdhci_prepare_data+0x2c/0x3a0
<4>[    4.014798]  [<c107a98b>] ? trace_hardirqs_off+0xb/0x10
<4>[    4.014827]  [<c13b6d3f>] ? _raw_spin_unlock_irqrestore+0x2f/0x60
<4>[    4.014854]  [<c1054fdd>] ? mod_timer+0x11d/0x380
<4>[    4.014880]  [<c12fc7db>] sdhci_send_command+0xdb/0x210
<4>[    4.014906]  [<c12fd5f3>] sdhci_request+0xc3/0x150
<4>[    4.014932]  [<c12ec56a>] mmc_start_request+0xda/0x200
<4>[    4.014960]  [<c120d7c2>] ? __raw_spin_lock_init+0x32/0x60
<4>[    4.014989]  [<c1066a85>] ? __init_waitqueue_head+0x35/0x50
<4>[    4.015015]  [<c12ec70b>] mmc_wait_for_req+0x7b/0x90
<4>[    4.015045]  [<c12f0c67>] mmc_send_cxd_data+0xf7/0x130
<4>[    4.015076]  [<c12ecbc0>] ? mmc_erase+0x140/0x140
<4>[    4.015102]  [<c12f139d>] mmc_send_ext_csd+0x1d/0x20
<4>[    4.015125]  [<c12efef0>] mmc_get_ext_csd+0x70/0x140
<4>[    4.015151]  [<c12effe8>] mmc_compare_ext_csds+0x28/0x190
<4>[    4.015176]  [<c12f039f>] mmc_init_card+0x24f/0x650
<4>[    4.015201]  [<c13b6d5d>] ? _raw_spin_unlock_irqrestore+0x4d/0x60
<4>[    4.015226]  [<c107fd9c>] ? trace_hardirqs_on_caller+0x11c/0x160
<4>[    4.015255]  [<c12f09a4>] mmc_attach_mmc+0xa4/0x190
<4>[    4.015282]  [<c12ee3f0>] mmc_rescan+0x210/0x240
<4>[    4.015311]  [<c105f9b6>] process_one_work+0x176/0x550
<4>[    4.015336]  [<c105f93a>] ? process_one_work+0xfa/0x550
<4>[    4.015360]  [<c12ee1e0>] ? mmc_init_erase+0x140/0x140
<4>[    4.015385]  [<c1061c2a>] worker_thread+0x12a/0x2c0
<4>[    4.015410]  [<c1061b00>] ? manage_workers.clone.18+0x100/0x100
<4>[    4.015437]  [<c1066244>] kthread+0x74/0x80
<4>[    4.015463]  [<c10661d0>] ? __init_kthread_worker+0x60/0x60
<4>[    4.015490]  [<c13b7dfa>] kernel_thread_helper+0x6/0xd
<0>[    4.015507] Code: 57 89 d7 56 53 89 c3 83 ec 10 8b 40 04 8b 72 28 f6 c4 10 89 45 f0 0f 85 91 00 00 00 85 f6 0f 84 c1 00 00 00 8b 4e 04 31 d2 89 c8 <f7> 73 58 ba d3 4d 62 10 89 c1 8b 06 f7 e2 c1 ea 06 01 d1 f7 45
<0>[    4.015829] EIP: [<c12fa38e>] sdhci_calc_timeout+0x2e/0x100 SS:ESP 0068:f5291c50

Reported-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-08-13 14:50:28 -04:00
..
accessibility
acpi Merge branch 'battery' into release 2011-08-05 22:16:42 -04:00
amba
ata Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2011-08-02 21:17:02 -10:00
atm
auxdisplay
base PM / Runtime: Allow _put_sync() from interrupts-disabled context 2011-08-05 21:45:20 +02:00
bcma
block
bluetooth
cdrom
char net: Compute protocol sequence numbers and fragment IDs using MD5. 2011-08-06 18:33:19 -07:00
clk
clocksource
connector proc_fork_connector: a lockless ->real_parent usage is not safe 2011-07-28 18:26:32 -07:00
cpufreq
cpuidle cpuidle: stop depending on pm_idle 2011-08-03 19:06:37 -04:00
crypto n2_crypto: Attach on Niagara-T3. 2011-07-28 01:30:07 -07:00
dca
dio
dma Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx 2011-08-04 16:43:43 -10:00
edac
eisa eisa/pci_eisa.c: fix BUG introduced by 005bdad7b8 2011-08-04 06:32:51 -10:00
firewire
firmware Merge branch 'pstore-efi' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6 2011-08-02 21:18:39 -10:00
gpio Merge branch 'gpio/next' of git://git.secretlab.ca/git/linux-2.6 2011-08-01 06:13:48 -10:00
gpu Revert "drm/i915: Try enabling RC6 by default (again)" 2011-08-05 10:56:29 +01:00
hid
hwmon Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging 2011-07-30 08:57:57 -10:00
hwspinlock
i2c
ide drivers/ide/cy82c693.c: Add missing pci_dev_put 2011-08-04 01:30:34 -07:00
idle
ieee802154
infiniband Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2011-07-27 13:21:40 -07:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2011-08-03 22:00:09 -10:00
iommu
isdn Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2011-07-28 05:58:19 -07:00
leds
lguest
macintosh
mca
md dm table: set flush capability based on underlying devices 2011-08-02 12:32:08 +01:00
media Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6 2011-07-30 00:08:53 -07:00
memstick
message Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 2011-07-30 08:36:02 -10:00
mfd mfd: Fix mismatch in twl4030 mutex lock-unlock 2011-07-31 23:28:27 +02:00
misc mmc: cb710: fix possible pci_dev leak in cb710_pci_configure() 2011-08-13 14:50:23 -04:00
mmc mmc: sdhci: check host->clock before using it as a denominator 2011-08-13 14:50:28 -04:00
mtd
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2011-08-05 06:42:01 -10:00
nfc
nubus
of Revert "dt: add of_alias_scan and of_alias_get_id" 2011-08-04 11:26:24 +01:00
oprofile
parisc
parport
pci Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2011-08-02 21:17:02 -10:00
pcmcia Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6 2011-07-31 06:23:08 -10:00
platform acer-wmi: support Lenovo ideapad S205 wifi switch 2011-08-05 15:21:52 -04:00
pnp
power Merge git://git.infradead.org/battery-2.6 2011-07-31 06:24:50 -10:00
pps
ps3
ptp
rapidio
regulator Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6 2011-08-01 14:05:46 -10:00
rtc rtc-omap: fix initialization of control register 2011-08-03 14:25:20 -10:00
s390 [S390] qdio: Use kstrtoul_from_user 2011-08-03 16:44:21 +02:00
sbus
scsi Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 2011-07-30 08:36:02 -10:00
sfi
sh Merge branch 'sh-latest' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-3.x 2011-08-01 06:10:16 -10:00
sn
spi spi/pl022: remove function cannot exit 2011-08-02 14:54:11 +01:00
ssb
staging Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6 2011-07-30 00:08:53 -07:00
target Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2011-08-03 15:12:09 -10:00
tc
telephony
thermal thermal: make THERMAL_HWMON implementation fully internal 2011-08-02 14:51:57 -04:00
tty sh: Fix boot crash related to SCI 2011-08-07 15:51:45 -07:00
uio
usb Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6 2011-07-30 00:08:53 -07:00
uwb
vhost
video savagedb: Fix typo causing regression in savage4 series video chip detection 2011-08-06 12:02:40 -07:00
virt
virtio
vlynq
w1
watchdog watchdog: Cleanup WATCHDOG_CORE help text 2011-08-02 08:23:07 +00:00
xen xen/self-balloon: Add dependency on tmem. 2011-08-03 14:34:57 -04:00
zorro
Kconfig
Makefile