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author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-12-31 13:03:05 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-12-31 13:03:05 -0800 |
commit | 52c90f2d32bfa7d6eccd66a56c44ace1f78fbadd (patch) | |
tree | b6e54081e8da0b050bd06cf51a311f6e11bd0c0a /arch/x86/include/asm/tlbflush.h | |
parent | cea92e843e40452c08ba313abc39f59efbb4c29c (diff) | |
parent | 7f414195b0c3612acd12b4611a5fe75995cf10c7 (diff) | |
download | linux-stable-52c90f2d32bfa7d6eccd66a56c44ace1f78fbadd.tar.gz linux-stable-52c90f2d32bfa7d6eccd66a56c44ace1f78fbadd.tar.bz2 linux-stable-52c90f2d32bfa7d6eccd66a56c44ace1f78fbadd.zip |
Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 page table isolation fixes from Thomas Gleixner:
"Four patches addressing the PTI fallout as discussed and debugged
yesterday:
- Remove stale and pointless TLB flush invocations from the hotplug
code
- Remove stale preempt_disable/enable from __native_flush_tlb()
- Plug the memory leak in the write_ldt() error path"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/ldt: Make LDT pgtable free conditional
x86/ldt: Plug memory leak in error path
x86/mm: Remove preempt_disable/enable() from __native_flush_tlb()
x86/smpboot: Remove stale TLB flush invocations
Diffstat (limited to 'arch/x86/include/asm/tlbflush.h')
-rw-r--r-- | arch/x86/include/asm/tlbflush.h | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index f68f9c836cca..4a08dd2ab32a 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -348,15 +348,17 @@ static inline void invalidate_user_asid(u16 asid) */ static inline void __native_flush_tlb(void) { - invalidate_user_asid(this_cpu_read(cpu_tlbstate.loaded_mm_asid)); /* - * If current->mm == NULL then we borrow a mm which may change - * during a task switch and therefore we must not be preempted - * while we write CR3 back: + * Preemption or interrupts must be disabled to protect the access + * to the per CPU variable and to prevent being preempted between + * read_cr3() and write_cr3(). */ - preempt_disable(); + WARN_ON_ONCE(preemptible()); + + invalidate_user_asid(this_cpu_read(cpu_tlbstate.loaded_mm_asid)); + + /* If current->mm == NULL then the read_cr3() "borrows" an mm */ native_write_cr3(__native_read_cr3()); - preempt_enable(); } /* |