diff options
Diffstat (limited to 'arch/x86/include/asm/processor.h')
| -rw-r--r-- | arch/x86/include/asm/processor.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index c7a4e2a174b9..617805981cce 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -316,7 +316,13 @@ struct x86_hw_tss { */ u64 sp1; + /* + * Since Linux does not use ring 2, the 'sp2' slot is unused by + * hardware. entry_SYSCALL_64 uses it as scratch space to stash + * the user RSP value. + */ u64 sp2; + u64 reserved2; u64 ist[7]; u32 reserved3; |