diff options
| -rw-r--r-- | arch/x86/include/asm/mmu_context.h | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h index 4b75d591eb5e..52c18359f1dc 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -55,12 +55,14 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, /* * Load the LDT, if the LDT is different. * - * It's possible leave_mm(prev) has been called. If so, - * then prev->context.ldt could be out of sync with the - * LDT descriptor or the LDT register. This can only happen - * if prev->context.ldt is non-null, since we never free - * an LDT. But LDTs can't be shared across mms, so - * prev->context.ldt won't be equal to next->context.ldt. + * It's possible that prev->context.ldt doesn't match + * the LDT register. This can happen if leave_mm(prev) + * was called and then modify_ldt changed + * prev->context.ldt but suppressed an IPI to this CPU. + * In this case, prev->context.ldt != NULL, because we + * never free an LDT while the mm still exists. That + * means that next->context.ldt != prev->context.ldt, + * because mms never share an LDT. */ if (unlikely(prev->context.ldt != next->context.ldt)) load_LDT_nolock(&next->context); |