Re: [PATCH 0/3] Fix and cleanup for 32-bit PV sysexit

From: Borislav Petkov
Date: Thu Nov 19 2015 - 07:11:03 EST

On Wed, Nov 18, 2015 at 03:06:16PM -0500, Boris Ostrovsky wrote:
> The first patch fixes Xen PV regression introduced by 32-bit rewrite. Unlike the
> earlier version it uses ALTERNATIVE instruction and avoids using xen_sysexit
> (and sysret32 in compat mode) pv ops, as suggested by Andy. (I ended up patching
> TEST with XOR to avoid extra NOPs, even though I said yesterday it would be
> wrong. It's not wrong)
>
> As result of this patch irq_enable_sysexit and usergs_sysret32 pv ops are not
> used anymore by anyone and so can be removed.
>
> Boris Ostrovsky (3):
> x86/xen: Avoid fast syscall path for Xen PV guests
> x86: irq_enable_sysexit pv op is no longer needed
> x86: usergs_sysret32 pv op is no longer needed
>
> arch/x86/entry/entry_32.S | 11 ++++-------
> arch/x86/entry/entry_64_compat.S | 16 ++++++----------
> arch/x86/include/asm/cpufeature.h | 1 +
> arch/x86/include/asm/paravirt.h | 12 ------------
> arch/x86/include/asm/paravirt_types.h | 17 -----------------
> arch/x86/kernel/asm-offsets.c | 3 ---
> arch/x86/kernel/asm-offsets_64.c | 1 -
> arch/x86/kernel/paravirt.c | 12 ------------
> arch/x86/kernel/paravirt_patch_32.c | 2 --
> arch/x86/kernel/paravirt_patch_64.c | 3 ---
> arch/x86/xen/enlighten.c | 7 +++----
> arch/x86/xen/xen-asm_32.S | 14 --------------
> arch/x86/xen/xen-asm_64.S | 19 -------------------
> arch/x86/xen/xen-ops.h | 3 ---
> 14 files changed, 14 insertions(+), 107 deletions(-)

Can't argue with that diffstat!

:-)

--
Regards/Gruss,
Boris.

SUSE Linux GmbH, GF: Felix ImendÃrffer, Jane Smithard, Graham Norton, HRB 21284 (AG NÃrnberg)
--
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/