Messages in this thread | | | Date | Tue, 24 Oct 2023 10:33:28 +0800 | From | "Hou Wenlong" <> | Subject | Re: [PATCH 1/2] x86/xen/pvh: Set up percpu for stack canary in 32-bit kernel entry |
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On Mon, Oct 23, 2023 at 08:02:02PM +0800, Andy Shevchenko wrote: > On Mon, Oct 23, 2023 at 12:10 PM Hou Wenlong > <houwenlong.hwl@antgroup.com> wrote: > > > > In a 32-bit SMP kernel, the stack canary is a percpu variable accessed > > as %fs:__stack_chk_guard. However, the ABI for PVH entry does not > > specify the %fs register state. It currently works because the initial > > %fs register is 0x10 for QEMU, which is the same as $PVH_DS_SEL. > > > %However, for added safety, the percpu should be set up explicitly > > %before calling xen_prepare_pvh(), which accesses the stack canary. > > Stray leading % in two lines above. > Oh, sorry for that. It was added by mistake by my editor, and I didn't carefully review it before sending.
Thanks!
> -- > With Best Regards, > Andy Shevchenko
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