Commit-ID: cb307113746b4d184155d2c412e8069aeaa60d42 Gitweb: http://git.kernel.org/tip/cb307113746b4d184155d2c412e8069aeaa60d42 Author: Michael Ellerman <mpe@xxxxxxxxxxxxxx> AuthorDate: Mon, 4 May 2015 16:26:39 +1000 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Fri, 8 May 2015 12:26:01 +0200 perf_event: Don't allow vmalloc() backed perf on powerpc On powerpc the perf event interrupt is not masked when interrupts are disabled, allowing it to function as an NMI. This causes problems if perf is using vmalloc. If we take a page fault on the vmalloc region the fault handler will fail the page fault because it detects we are coming in from an NMI (see do_hash_page()). We don't actually need or want vmalloc backed perf so just disable it on powerpc. Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: <linuxppc-dev@xxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxx> Cc: Anton Blanchard <anton@xxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: acme@xxxxxxxxxxxxxxxxxx Cc: sukadev@xxxxxxxxxxxxxxxxxx Link: http://lkml.kernel.org/r/1430720799-18426-1-git-send-email-mpe@xxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- init/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/init/Kconfig b/init/Kconfig index dc24dec..81050e4 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1637,7 +1637,7 @@ config PERF_EVENTS config DEBUG_PERF_USE_VMALLOC default n bool "Debug: use vmalloc to back perf mmap() buffers" - depends on PERF_EVENTS && DEBUG_KERNEL + depends on PERF_EVENTS && DEBUG_KERNEL && !PPC select PERF_USE_VMALLOC help Use vmalloc memory to back perf mmap() buffers. -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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