Re: [PATCH] ARM: fix input-only operand modification in load_unaligned_zeropad()

On Thu, Nov 27, 2025 at 10:58:48AM +0800, Liyuan Pang wrote:

In the inline assembly inside load_unaligned_zeropad(), the "addr" is
constrained as input-only operand. The compiler assumes that on exit
from the asm statement these operands contain the same values as they
had before executing the statement, but when kernel page fault happened,
the assembly fixup code "bic %2 %2, #0x3" modify the value of "addr",
which may lead to an unexpected behavior.

Use a temporary variable "tmp" to handle it, instead of modifying the
input-only operand, just like what arm64's load_unaligned_zeropad()
does.

Fixes: b9a50f74905a ("ARM: 7450/1: dcache: select DCACHE_WORD_ACCESS for little-endian ARMv6+ CPUs")

Co-developed-by: Xie Yuanbin <redacted>
Signed-off-by: Xie Yuanbin <redacted>
Signed-off-by: Liyuan Pang <redacted>

Sorry, I missed this email in the deluge. This looks entirely correct.
Please submit this to the patch system. Details in the signature below.
Thanks.

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