Messages in this thread | ![/](/images/icornerl.gif) | | Date | Wed, 11 Jan 2023 14:59:02 -0800 | From | "H. Peter Anvin" <> | Subject | Re: x86/boot: Avoid using Intel mnemonics in AT&T syntax asm |
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On January 10, 2023 3:35:50 AM PST, Ingo Molnar <mingo@kernel.org> wrote: > >* Peter Zijlstra <peterz@infradead.org> wrote: > >> >> With 'GNU assembler (GNU Binutils for Debian) 2.39.90.20221231' the >> build now reports: >> >> arch/x86/realmode/rm/../../boot/bioscall.S: Assembler messages: >> arch/x86/realmode/rm/../../boot/bioscall.S:35: Warning: found `movsd'; assuming `movsl' was meant >> arch/x86/realmode/rm/../../boot/bioscall.S:70: Warning: found `movsd'; assuming `movsl' was meant >> >> arch/x86/boot/bioscall.S: Assembler messages: >> arch/x86/boot/bioscall.S:35: Warning: found `movsd'; assuming `movsl' was meant >> arch/x86/boot/bioscall.S:70: Warning: found `movsd'; assuming `movsl' was meant >> >> Which is due to: >> >> PR gas/29525 >> >> Note that with the dropped CMPSD and MOVSD Intel Syntax string insn >> templates taking operands, mixed IsString/non-IsString template groups >> (with memory operands) cannot occur anymore. With that >> maybe_adjust_templates() becomes unnecessary (and is hence being >> removed). >> >> More details: https://sourceware.org/bugzilla/show_bug.cgi?id=29525 >> >> Fixes: 7a734e7dd93b ("x86, setup: "glove box" BIOS calls -- infrastructure") >> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> >> --- >> arch/x86/boot/bioscall.S | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> --- a/arch/x86/boot/bioscall.S >> +++ b/arch/x86/boot/bioscall.S >> @@ -32,7 +32,7 @@ >> movw %dx, %si >> movw %sp, %di >> movw $11, %cx >> - rep; movsd >> + rep; movsl >> >> /* Pop full state from the stack */ >> popal >> @@ -67,7 +67,7 @@ >> jz 4f >> movw %sp, %si >> movw $11, %cx >> - rep; movsd >> + rep; movsl >> 4: addw $44, %sp > >So I think the GAS change to introduce this warning was probably >unnecessary - these instructions weren't really causing any trouble and the >syntax was basically a legacy thing that shouldn't be touched - but I guess >that argument is water down the bridge now: > > Reviewed-by: Ingo Molnar <mingo@kernel.org> > >Thanks, > > Ingo
Yeah; looks like a gas bug/regression, but there isn't really any reason not to fix it.
The semicolon after rep isn't needed anymore either ;)
Acked-by: H. Peter Anvin (Intel) <hpa@zytor.com>
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