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. -- 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
