Messages in this thread | | | Date | Fri, 02 May 2014 14:44:33 -0700 | From | "H. Peter Anvin" <> | Subject | Re: [RFC/HACK] x86: Fast return to kernel |
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On 05/02/2014 02:42 PM, Andy Lutomirski wrote: > > Hah -- I think I just faked both of you out :) > > I don't think this has anything to do with the error code, and I think > that the errorentry code already does more or less that: it pushes -1. > > The real issue here is probably the magic 16-byte stack alignment when > a non-stack-switching interrupt happens. >
Errorentry is when there *is* an error code pushed by the hardware. The other variant is zeroentry, which does generate a zero error code -- eventually. The -1 means we didn't enter the kernel through a system call.
-hpa
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