Re: [PATCH] x86/cpu: Fix SMAP check in PVOPS environments

[Ingo Molnar]

* Rusty Russell <rusty@xxxxxxxxxxxxxxx> wrote:

> As the comment in arch/x86/include/asm/paravirt_types.h says:
> 
> 	 * Get/set interrupt state.  save_fl and restore_fl are only
> 	 * expected to use X86_EFLAGS_IF; all other bits
> 	 * returned from save_fl are undefined, and may be ignored by
> 	 * restore_fl.

There should be no 'may' about this: under CONFIG_PARAVIRT_DEBUG=y the reminder of 
the flags should be cleared (or all bits should be set: that will instantly crash 
if restored verbatim), so that we trip up generic code that relies on non-IF 
restoration?

Thanks,

	Ingo
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