mirror of https://gitee.com/openkylin/linux.git
8a9949bc71
Xen's raw SYSCALL entries are much less weird than native. Rather than fudging them to look like native entries, use the Xen-provided stack frame directly. This lets us eliminate entry_SYSCALL_64_after_swapgs and two uses of the SWAPGS_UNSAFE_STACK paravirt hook. The SYSENTER code would benefit from similar treatment. This makes one change to the native code path: the compat instruction that clears the high 32 bits of %rax is moved slightly later. I'd be surprised if this affects performance at all. Tested-by: Juergen Gross <jgross@suse.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/7c88ed36805d36841ab03ec3b48b4122c4418d71.1502164668.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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| .. | ||
| syscalls | ||
| vdso | ||
| vsyscall | ||
| Makefile | ||
| calling.h | ||
| common.c | ||
| entry_32.S | ||
| entry_64.S | ||
| entry_64_compat.S | ||
| syscall_32.c | ||
| syscall_64.c | ||
| thunk_32.S | ||
| thunk_64.S | ||