Re: [PATCH for 4.9/4.14] powerpc: Fix incorrect stw{, ux, u, x} instructions in __set_pte_at
From: Sasha Levin <sashal@kernel.org>
Date: 2021-01-13 16:49:28
Also in:
lkml, stable
On Wed, Jan 13, 2021 at 07:12:44AM +0000, Christophe Leroy wrote:
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Backport for 4.9 and 4.14
(cherry picked from commit d85be8a49e733dcd23674aa6202870d54bf5600d)
The placeholder for instruction selection should use the second
argument's operand, which is %1, not %0. This could generate incorrect
assembly code if the memory addressing of operand %0 is a different
form from that of operand %1.
Also remove the %Un placeholder because having %Un placeholders
for two operands which are based on the same local var (ptep) doesn't
make much sense. By the way, it doesn't change the current behaviour
because "<>" constraint is missing for the associated "=m".
[chleroy: revised commit log iaw segher's comments and removed %U0]
Fixes: 9bf2b5cdc5fe ("powerpc: Fixes for CONFIG_PTE_64BIT for SMP support")
Cc: <redacted> # v2.6.28+
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Christophe Leroy <redacted>
Acked-by: Segher Boessenkool <redacted>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/96354bd77977a6a933fe9020da57629007fdb920.1603358942.git.christophe.leroy@csgroup.eu (local)I took this and the 4.4 backport, thanks! -- Thanks, Sasha