Messages in this thread | | | From | Andy Lutomirski <> | Date | Wed, 16 Jan 2019 16:09:52 -0800 | Subject | Re: [PATCH v3] x86-64/Xen: fix stack switching |
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On Tue, Jan 15, 2019 at 8:58 AM Jan Beulich <JBeulich@suse.com> wrote: > > While in the native case entry into the kernel happens on the trampoline > stack, PV Xen kernels get entered with the current thread stack right > away. Hence source and destination stacks are identical in that case, > and special care is needed. > > Other than in sync_regs() the copying done on the INT80 path isn't > NMI / #MC safe, as either of these events occurring in the middle of the > stack copying would clobber data on the (source) stack. > > I'm not altering the similar code in interrupt_entry() and nmi(), as > those code paths are unreachable afaict when running PV Xen guests.
Acked-by: Andy Lutomirski <luto@kernel.org>
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