linux/arch
Nathan Lynch e610a466d1 powerpc/pseries/mobility: rebuild cacheinfo hierarchy post-migration
It's common for the platform to replace the cache device nodes after a
migration. Since the cacheinfo code is never informed about this, it
never drops its references to the source system's cache nodes, causing
it to wind up in an inconsistent state resulting in warnings and oopses
as soon as CPU online/offline occurs after the migration, e.g.

  cache for /cpus/l3-cache@3113(Unified) refers to cache for /cpus/l2-cache@200d(Unified)
  WARNING: CPU: 15 PID: 86 at arch/powerpc/kernel/cacheinfo.c:176 release_cache+0x1bc/0x1d0
  [...]
  NIP release_cache+0x1bc/0x1d0
  LR  release_cache+0x1b8/0x1d0
  Call Trace:
    release_cache+0x1b8/0x1d0 (unreliable)
    cacheinfo_cpu_offline+0x1c4/0x2c0
    unregister_cpu_online+0x1b8/0x260
    cpuhp_invoke_callback+0x114/0xf40
    cpuhp_thread_fun+0x270/0x310
    smpboot_thread_fn+0x2c8/0x390
    kthread+0x1b8/0x1c0
    ret_from_kernel_thread+0x5c/0x68

Using device tree notifiers won't work since we want to rebuild the
hierarchy only after all the removals and additions have occurred and
the device tree is in a consistent state. Call cacheinfo_teardown()
before processing device tree updates, and rebuild the hierarchy
afterward.

Fixes: 410bccf978 ("powerpc/pseries: Partition migration in the kernel")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-06-15 16:52:37 +10:00
..
alpha treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47 2019-05-24 17:27:13 +02:00
arc treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
arm The usual smattering of fixes and tunings that came in too late for the 2019-05-26 13:45:15 -07:00
arm64 The usual smattering of fixes and tunings that came in too late for the 2019-05-26 13:45:15 -07:00
c6x treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36 2019-05-24 17:27:11 +02:00
csky treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
h8300 treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
hexagon treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
ia64 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47 2019-05-24 17:27:13 +02:00
m68k treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 74 2019-05-24 17:36:47 +02:00
microblaze treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
mips treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 102 2019-05-24 17:39:00 +02:00
nds32 treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
nios2 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13 2019-05-21 11:28:45 +02:00
openrisc treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
parisc treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
powerpc powerpc/pseries/mobility: rebuild cacheinfo hierarchy post-migration 2019-06-15 16:52:37 +10:00
riscv treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 120 2019-05-24 17:39:02 +02:00
s390 KVM: s390: fix memory slot handling for KVM_SET_USER_MEMORY_REGION 2019-05-24 21:27:14 +02:00
sh treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
sparc treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61 2019-05-24 17:36:45 +02:00
um treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
unicore32 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-05-19 10:23:24 -07:00
x86 The usual smattering of fixes and tunings that came in too late for the 2019-05-26 13:45:15 -07:00
xtensa treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
.gitignore
Kconfig Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-05-16 11:00:20 -07:00