6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jesse Taube <jesse@xxxxxxxxxxxx>
commit 9c528b5f7927b857b40f3c46afbc869827af3c94 upstream.
The check_unaligned_access_emulated() function should have been called
during CPU hotplug to ensure that if all CPUs had emulated unaligned
accesses, the new CPU also does.
This patch adds the call to check_unaligned_access_emulated() in
the hotplug path.
Fixes: 55e0bf49a0d0 ("RISC-V: Probe misaligned access speed in parallel")
Signed-off-by: Jesse Taube <jesse@xxxxxxxxxxxx>
Reviewed-by: Evan Green <evan@xxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20241017-jesse_unaligned_vector-v10-2-5b33500160f8@xxxxxxxxxxxx
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/riscv/kernel/unaligned_access_speed.c | 1 +
1 file changed, 1 insertion(+)
--- a/arch/riscv/kernel/unaligned_access_speed.c
+++ b/arch/riscv/kernel/unaligned_access_speed.c
@@ -191,6 +191,7 @@ static int riscv_online_cpu(unsigned int
if (per_cpu(misaligned_access_speed, cpu) != RISCV_HWPROBE_MISALIGNED_SCALAR_UNKNOWN)
goto exit;
+ check_unaligned_access_emulated(NULL);
buf = alloc_pages(GFP_KERNEL, MISALIGNED_BUFFER_ORDER);
if (!buf) {
pr_warn("Allocation failure, not measuring misaligned performance\n");
