x86/entry/64: Fix entry_SYSCALL_64_after_hwframe() IRQ tracing
When I added entry_SYSCALL_64_after_hwframe(), I left TRACE_IRQS_OFF before it. This means that users of entry_SYSCALL_64_after_hwframe() were responsible for invoking TRACE_IRQS_OFF, and the one and only user (Xen, added in the same commit) got it wrong. I think this would manifest as a warning if a Xen PV guest with CONFIG_DEBUG_LOCKDEP=y were used with context tracking. (The context tracking bit is to cause lockdep to get invoked before we turn IRQs back on.) I haven't tested that for real yet because I can't get a kernel configured like that to boot at all on Xen PV. Move TRACE_IRQS_OFF below the label. Signed-off-by: NAndy Lutomirski <luto@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Fixes: 8a9949bc ("x86/xen/64: Rearrange the SYSCALL entries") Link: http://lkml.kernel.org/r/9150aac013b7b95d62c2336751d5b6e91d2722aa.1511325444.git.luto@kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
Showing
想要评论请 注册 或 登录