diff mbox series

[v4,03/10] arm64: cpufeature: Correctly display signed override values

Message ID 20240122181344.258974-4-maz@kernel.org (mailing list archive)
State New, archived
Headers show
Series arm64: Add support for FEAT_E2H0, or lack thereof | expand

Commit Message

Marc Zyngier Jan. 22, 2024, 6:13 p.m. UTC 
When a field gets overriden, the kernel indicates the result of
the override in dmesg. This works well with unsigned fields, but
results in a pretty ugly output when the field is signed.

Truncate the field to its width before displaying it.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/kernel/cpufeature.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Catalin Marinas Feb. 8, 2024, 12:14 p.m. UTC | #1 
On Mon, Jan 22, 2024 at 06:13:37PM +0000, Marc Zyngier wrote:
> When a field gets overriden, the kernel indicates the result of
> the override in dmesg. This works well with unsigned fields, but
> results in a pretty ugly output when the field is signed.
> 
> Truncate the field to its width before displaying it.
> 
> Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> Signed-off-by: Marc Zyngier <maz@kernel.org>

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
diff mbox series

Patch

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 92b1546f2622..bae5d0655262 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -949,7 +949,8 @@  static void init_cpu_ftr_reg(u32 sys_reg, u64 new)
 				pr_warn("%s[%d:%d]: %s to %llx\n",
 					reg->name,
 					ftrp->shift + ftrp->width - 1,
-					ftrp->shift, str, tmp);
+					ftrp->shift, str,
+					tmp & (BIT(ftrp->width) - 1));
 		} else if ((ftr_mask & reg->override->val) == ftr_mask) {
 			reg->override->val &= ~ftr_mask;
 			pr_warn("%s[%d:%d]: impossible override, ignored\n",