linux_dsm_epyc7002/arch
Bharat Bhushan 09000adb86 KVM: PPC: Fix issue clearing exit timing counters
Following dump is observed on host when clearing the exit timing counters

[root@p1021mds kvm]# echo -n 'c' > vm1200_vcpu0_timing
INFO: task echo:1276 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
echo          D 0ff5bf94     0  1276   1190 0x00000000
Call Trace:
[c2157e40] [c0007908] __switch_to+0x9c/0xc4
[c2157e50] [c040293c] schedule+0x1b4/0x3bc
[c2157e90] [c04032dc] __mutex_lock_slowpath+0x74/0xc0
[c2157ec0] [c00369e4] kvmppc_init_timing_stats+0x20/0xb8
[c2157ed0] [c0036b00] kvmppc_exit_timing_write+0x84/0x98
[c2157ef0] [c00b9f90] vfs_write+0xc0/0x16c
[c2157f10] [c00ba284] sys_write+0x4c/0x90
[c2157f40] [c000e320] ret_from_syscall+0x0/0x3c

        The vcpu->mutex is used by kvm_ioctl_* (KVM_RUN etc) and same was
used when clearing the stats (in kvmppc_init_timing_stats()). What happens
is that when the guest is idle then it held the vcpu->mutx. While the
exiting timing process waits for guest to release the vcpu->mutex and
a hang state is reached.

        Now using seprate lock for exit timing stats.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:04 -04:00
..
alpha alpha: Fix uninitialized value in read_persistent_clock. 2011-04-17 14:41:30 -07:00
arm Merge branch 'master' of ssh://master.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into perf/urgent 2011-05-06 08:11:28 +02:00
avr32 avr32: add ATAG_BOARDINFO 2011-04-13 15:46:59 +02:00
blackfin Blackfin: SMP: fix cache flush loop 2011-04-13 19:34:06 -04:00
cris Fix common misspellings 2011-03-31 11:26:23 -03:00
frv Fix common misspellings 2011-03-31 11:26:23 -03:00
h8300 genirq: Remove the now obsolete config options and select statements 2011-03-30 14:13:23 +02:00
ia64 Merge branch 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6 2011-04-07 11:14:49 -07:00
m32r Fix common misspellings 2011-03-31 11:26:23 -03:00
m68k m68k/mm: Set all online nodes in N_NORMAL_MEMORY 2011-04-27 17:36:00 +02:00
microblaze usb: Fix Kconfig unmet dependencies for Microblaze EHCI 2011-04-13 15:43:59 -07:00
mips MIPS: Alchemy: fix xxs1500 build error 2011-05-10 18:15:26 +01:00
mn10300 Fix common misspellings 2011-03-31 11:26:23 -03:00
parisc [PARISC] set memory ranges in N_NORMAL_MEMORY when onlined 2011-04-21 09:32:38 -05:00
powerpc KVM: PPC: Fix issue clearing exit timing counters 2011-05-11 07:57:04 -04:00
s390 [S390] irqstats: fix counting of pfault, dasd diag and virtio irqs 2011-04-29 10:42:25 +02:00
score Fix common misspellings 2011-03-31 11:26:23 -03:00
sh sh, hw_breakpoints: Fix racy access to ptrace breakpoints 2011-04-25 17:36:12 +02:00
sparc Merge branch 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6 2011-04-07 11:14:49 -07:00
tile Fix common misspellings 2011-03-31 11:26:23 -03:00
um um: adjust current_thread_info() for newer gcc versions 2011-04-28 11:28:21 -07:00
unicore32 Merge branch 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6 2011-04-07 11:14:49 -07:00
x86 KVM: MMU: remove mmu_seq verification on pte update path 2011-05-11 07:57:03 -04:00
xtensa xtensa: Fixup irq conversion fallout and nmi_count 2011-04-20 00:32:09 +02:00
.gitignore
Kconfig oprofile, s390: Cleanups 2011-03-16 14:30:40 +01:00