[PATCH] x86/mm, KVM: fix warning when !CONFIG_PREEMPT_COUNT

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Recent commit d6e41f1151fe ("x86/mm, KVM: Teach KVM's VMX code that CR3
isn't a constant") introduced a VM_WARN_ON(!in_atomic()) which generates
false positives on every vm entry on !CONFIG_PREEMPT_COUNT kernels.

Replace it with a test for preemptible(), which appears to match the
original intent and works across different CONFIG_PREEMPT* variations.

Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bpetkov@xxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Nadav Amit <nadav.amit@xxxxxxxxx>
Cc: Nadav Amit <namit@xxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Radim Krčmář <rkrcmar@xxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: X86 ML <x86@xxxxxxxxxx>
Cc: kvm@xxxxxxxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Fixes: d6e41f1151fe ("x86/mm, KVM: Teach KVM's VMX code that CR3 isn't a constant")
Signed-off-by: Roman Kagan <rkagan@xxxxxxxxxxxxx>
---
 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 ecfcb6643c9b..265c907d7d4c 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -293,7 +293,7 @@ static inline unsigned long __get_current_cr3_fast(void)
 	unsigned long cr3 = __pa(this_cpu_read(cpu_tlbstate.loaded_mm)->pgd);
 
 	/* For now, be very restrictive about when this can be called. */
-	VM_WARN_ON(in_nmi() || !in_atomic());
+	VM_WARN_ON(in_nmi() || preemptible());
 
 	VM_BUG_ON(cr3 != __read_cr3());
 	return cr3;
-- 
2.13.3

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>



[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [eCos]     [Asterisk Internet PBX]     [Linux API]
  Powered by Linux