Messages in this thread | | | Subject | Re: [Xen-devel] [PATCH v3 4/4] x86/asm: Rewrite sync_core() to use IRET-to-self | From | "H. Peter Anvin" <> | Date | Tue, 6 Dec 2016 11:32:00 -0800 |
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On 12/06/16 00:46, Jan Beulich wrote: >> + >> +#ifdef CONFIG_X86_32 >> + asm volatile ( >> + "pushfl\n\t" >> + "pushl %%cs\n\t" >> + "pushl $1f\n\t" >> + "iret\n\t" >> + "1:" >> + : "+r" (__sp) : : "cc", "memory"); > > I don't thing EFLAGS (i.e. "cc") gets modified anywhere here. And > the memory clobber would perhaps better be pulled out into an > explicit barrier() invocation (making it more obvious what it's needed > for)? >
Not to mention "cc" doesn't do anything on x86 at all.
-hpa
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