On 09/08/17 11:35, Peter Zijlstra wrote: > On Wed, Aug 09, 2017 at 11:24:07AM +0200, Juergen Gross wrote: >> On 09/08/17 11:16, Peter Zijlstra wrote: >>> On Wed, Aug 09, 2017 at 10:49:43AM +0200, Juergen Gross wrote: >>>>> ALTERNATIVE "pushfq; popq %rax", "callq *pv_irq_ops.save_fl", >>>>> X86_FEATURE_GODDAMN_PV_IRQ_OPS >>>> >>>> You are aware that at least some of the Xen irq pvops functionality is >>>> patched inline? Your modification would slow down pv guests quite a >>>> bit, I guess. >>> >>> Where does that live? I know of the inline patching for native, but >>> didn't know the guests did any of that too. >> >> See arch/x86/xen/enlighten_pv.c xen_patch(). > > 'obvious' name that :-) I see that the actual code that's patched in > lives in xen-asm.S which unlike the native case doesn't appear to have > its own section. So that might make things even more difficult. I don't see why this couldn't be changed. Juergen -- To unsubscribe from this list: send the line "unsubscribe live-patching" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
