From df2ffeda6370a77011902e7c9d7a1eb1cbffed4f Mon Sep 17 00:00:00 2001 From: John David Anglin Date: Fri, 19 Nov 2021 22:18:47 +0100 Subject: [PATCH] parisc: Fix extraction of hash lock bits in syscall.S The extru instruction leaves the most significant 32 bits of the target register in an undefined state on PA 2.0 systems. If any of these bits are nonzero, this will break the calculation of the lock pointer. Fix by using extrd,u instruction via extru_safe macro on 64-bit kernels. Signed-off-by: John David Anglin Signed-off-by: Helge Deller --- arch/parisc/kernel/syscall.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S index 4fb3b6a993bf..d2497b339d13 100644 --- a/arch/parisc/kernel/syscall.S +++ b/arch/parisc/kernel/syscall.S @@ -566,7 +566,7 @@ lws_compare_and_swap: ldo R%lws_lock_start(%r20), %r28 /* Extract eight bits from r26 and hash lock (Bits 3-11) */ - extru %r26, 28, 8, %r20 + extru_safe %r26, 28, 8, %r20 /* Find lock to use, the hash is either one of 0 to 15, multiplied by 16 (keep it 16-byte aligned) @@ -751,7 +751,7 @@ cas2_lock_start: ldo R%lws_lock_start(%r20), %r28 /* Extract eight bits from r26 and hash lock (Bits 3-11) */ - extru %r26, 28, 8, %r20 + extru_safe %r26, 28, 8, %r20 /* Find lock to use, the hash is either one of 0 to 15, multiplied by 16 (keep it 16-byte aligned)