diff options
| author | Wolfram Sang <wsa@kernel.org> | 2020-07-31 15:54:27 +0200 |
|---|---|---|
| committer | Wolfram Sang <wsa@kernel.org> | 2020-07-31 15:54:27 +0200 |
| commit | 073d398dc4841f62488ac6060ffeb9dfce6e0a98 (patch) | |
| tree | 2ae9d508d0cd27f02584b9befb063dda5cb11a0b /arch/x86/include/asm/io_bitmap.h | |
| parent | afca861bc6a3141c858d08279eb9afca76584fa6 (diff) | |
| parent | 92ed301919932f777713b9172e525674157e983d (diff) | |
Merge tag 'v5.8-rc7' into i2c/for-5.9
Diffstat (limited to 'arch/x86/include/asm/io_bitmap.h')
| -rw-r--r-- | arch/x86/include/asm/io_bitmap.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/arch/x86/include/asm/io_bitmap.h b/arch/x86/include/asm/io_bitmap.h index ac1a99ffbd8d..7f080f5c7def 100644 --- a/arch/x86/include/asm/io_bitmap.h +++ b/arch/x86/include/asm/io_bitmap.h @@ -19,12 +19,28 @@ struct task_struct; void io_bitmap_share(struct task_struct *tsk); void io_bitmap_exit(struct task_struct *tsk); +static inline void native_tss_invalidate_io_bitmap(void) +{ + /* + * Invalidate the I/O bitmap by moving io_bitmap_base outside the + * TSS limit so any subsequent I/O access from user space will + * trigger a #GP. + * + * This is correct even when VMEXIT rewrites the TSS limit + * to 0x67 as the only requirement is that the base points + * outside the limit. + */ + this_cpu_write(cpu_tss_rw.x86_tss.io_bitmap_base, + IO_BITMAP_OFFSET_INVALID); +} + void native_tss_update_io_bitmap(void); #ifdef CONFIG_PARAVIRT_XXL #include <asm/paravirt.h> #else #define tss_update_io_bitmap native_tss_update_io_bitmap +#define tss_invalidate_io_bitmap native_tss_invalidate_io_bitmap #endif #else |