RE: [PATCH] x86: bitops: fix build regression

On May 7, 2020 12:44:44 AM PDT, David Laight David.Laight@ACULAB.COM wrote:

From: Brian Gerst

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Sent: 07 May 2020 07:18

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--- a/arch/x86/include/asm/bitops.h +++ b/arch/x86/include/asm/bitops.h @@ -54,7 +54,7 @@ arch_set_bit(long nr, volatile unsigned long

*addr)

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    if (__builtin_constant_p(nr)) {
            asm volatile(LOCK_PREFIX "orb %1,%0"
                    : CONST_MASK_ADDR(nr, addr)

•                   : "iq" (CONST_MASK(nr) & 0xff)
  

•                   : "iq" ((u8)(CONST_MASK(nr) & 0xff))
  

I think a better fix would be to make CONST_MASK() return a u8 value rather than have to cast on every use.

Or assign to a local variable - then it doesn't matter how the value is actually calculated. So: u8 mask = CONST_MASK(nr); asm volatile(LOCK_PREFIX "orb %1,%0" : CONST_MASK_ADDR(nr, addr) : "iq" mask

David

Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)

"const u8" please...