Messages in this thread Patch in this message | | | Date | Thu, 9 Jul 2015 19:23:38 +0200 | From | Peter Zijlstra <> | Subject | [PATCH] x86: Fix static_key in load_mm_cr4() |
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Mikulas reported his K6-3 not booting. This is because the static_key confusion struck and bit Andy, this wants to be static_key_false().
Fixes: a66734297f78 ("perf/x86: Add /sys/devices/cpu/rdpmc=2 to allow rdpmc for all tasks") Cc: Andy Lutomirski <luto@amacapital.net> Reported-by: Mikulas Patocka <mpatocka@redhat.com> Tested-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> --- arch/x86/include/asm/mmu_context.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h index 5e8daee7c5c9..804a3a6030ca 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -23,7 +23,7 @@ extern struct static_key rdpmc_always_available; static inline void load_mm_cr4(struct mm_struct *mm) { - if (static_key_true(&rdpmc_always_available) || + if (static_key_false(&rdpmc_always_available) || atomic_read(&mm->context.perf_rdpmc_allowed)) cr4_set_bits(X86_CR4_PCE); else
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