linux/arch/powerpc
Madhavan Srinivasan 249fad734a powerpc/perf: Disable trace_imc pmu
When a root user or a user with CAP_SYS_ADMIN privilege uses any
trace_imc performance monitoring unit events, to monitor application
or KVM threads, it may result in a checkstop (System crash).

The cause is frequent switching of the "trace/accumulation" mode of
the In-Memory Collection hardware (LDBAR).

This patch disables the trace_imc PMU unit entirely to avoid
triggering the checkstop. A future patch will reenable it at a later
stage once a workaround has been developed.

Fixes: 012ae24484 ("powerpc/perf: Trace imc PMU functions")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Tested-by: Hariharan T.S. <hari@linux.ibm.com>
[mpe: Add pr_info_once() so dmesg shows the PMU has been disabled]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191118034452.9939-1-maddy@linux.vnet.ibm.com
2019-12-05 17:06:40 +11:00
..
boot Devicetree updates for v5.5: 2019-12-02 11:41:35 -08:00
configs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2019-12-01 13:26:18 -08:00
crypto powerpc updates for 5.5 2019-11-30 14:35:43 -08:00
include powerpc/archrandom: fix arch_get_random_seed_int() 2019-12-05 08:21:16 +11:00
kernel powerpc: Fix vDSO clock_getres() 2019-12-05 00:13:55 +11:00
kexec powerpc: Avoid clang warnings around setjmp and longjmp 2019-11-25 21:45:43 +11:00
kvm powerpc fixes for Spectre-RSB 2019-11-27 11:25:04 -08:00
lib powerpc/pmem: Convert to EXPORT_SYMBOL_GPL 2019-12-05 09:17:42 +11:00
math-emu
mm powerpc/pmem: Fix kernel crash due to wrong range value usage in flush_dcache_range 2019-12-05 00:11:45 +11:00
net powerpc/bpf: Fix tail call implementation 2019-11-02 00:32:26 +01:00
oprofile
perf powerpc updates for 5.5 2019-11-30 14:35:43 -08:00
platforms powerpc/perf: Disable trace_imc pmu 2019-12-05 17:06:40 +11:00
purgatory
sysdev powerpc/xive: Skip ioremap() of ESB pages for LSI interrupts 2019-12-05 00:11:45 +11:00
tools powerpc/tools: Don't quote $objdump in scripts 2019-10-30 22:55:12 +11:00
xmon powerpc: Avoid clang warnings around setjmp and longjmp 2019-11-25 21:45:43 +11:00
Kbuild powerpc/kexec: Move kexec files into a dedicated subdir. 2019-11-21 15:41:34 +11:00
Kconfig powerpc: Add support for GENERIC_EARLY_IOREMAP 2019-11-19 19:38:38 +11:00
Kconfig.debug powerpc: Fix Kconfig indentation 2019-11-25 21:45:43 +11:00
Makefile powerpc: Don't add -mabi= flags when building with Clang 2019-11-25 21:45:43 +11:00
Makefile.postlink kbuild: add $(BASH) to run scripts with bash-extension 2019-09-04 22:54:13 +09:00