Re: [PATCH] x86/insn: Fix vector instructions decoding on big endian

From: Masami Hiramatsu
Date: Wed Nov 25 2020 - 11:28:00 EST


On Tue, 24 Nov 2020 14:33:10 +0100
Vasily Gorbik <gor@xxxxxxxxxxxxx> wrote:

> On Fri, Nov 13, 2020 at 11:30:52AM -0600, Josh Poimboeuf wrote:
> > On Fri, Nov 13, 2020 at 05:09:54PM +0100, Vasily Gorbik wrote:
> > > Running instruction decoder posttest on s390 with allyesconfig shows
> > > errors. Instructions used in couple of kernel objects could not be
> > > correctly decoded on big endian system.
> > >
> > > insn_decoder_test: warning: objdump says 6 bytes, but insn_get_length() says 5
> > > insn_decoder_test: warning: Found an x86 instruction decoder bug, please report this.
> > > insn_decoder_test: warning: ffffffff831eb4e1: 62 d1 fd 48 7f 04 24 vmovdqa64 %zmm0,(%r12)
> > > insn_decoder_test: warning: objdump says 7 bytes, but insn_get_length() says 6
> > > insn_decoder_test: warning: Found an x86 instruction decoder bug, please report this.
> > > insn_decoder_test: warning: ffffffff831eb4e8: 62 51 fd 48 7f 44 24 01 vmovdqa64 %zmm8,0x40(%r12)
> > > insn_decoder_test: warning: objdump says 8 bytes, but insn_get_length() says 6
> > >
> > > This is because in few places instruction field bytes are set directly
> > > with further usage of "value". To address that introduce and use
> > > insn_set_byte() helper, which correctly updates "value" on big endian
> > > systems.
> > >
> > > Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
> > > ---
> > > Please let me know if this patch is good as it is or I should squash it
> > > into the patch 2 of my patch series and resend it again.
> >
> > It all looks good to me, thanks!
> >
> > Masami, does this patch look good, and also patches 1-2 of the series?
> > (I think you previously ACKed patch 2).
> >
>
> Friendly ping...

Sorry for replying late.
Yes, I think this series and the last patch look good to me.

Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>

for this series.

Thank you!


--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>