Re: [PATCH] powerpc/dt_cpu_ftrs: Avoid separate strlen() in scan_callback()
From: David Laight <hidden>
Date: 2026-07-01 09:42:06
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On Tue, 30 Jun 2026 17:46:56 +0200 Thorsten Blum [off-list ref] wrote:
quoted hunk ↗ jump to hunk
Use the return value of strscpy() when copying the display name instead of checking the source string length with strlen() first. Keep dt_cpu_name static but move it into dt_cpu_ftrs_scan_callback(), where it is assigned. Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> --- arch/powerpc/kernel/dt_cpu_ftrs.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-)diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c b/arch/powerpc/kernel/dt_cpu_ftrs.c index 3af6c06af02f..8d8e94e4d2bc 100644 --- a/arch/powerpc/kernel/dt_cpu_ftrs.c +++ b/arch/powerpc/kernel/dt_cpu_ftrs.c@@ -90,8 +90,6 @@ static void __restore_cpu_cpufeatures(void) init_pmu_registers(); } -static char dt_cpu_name[64]; - static struct cpu_spec __initdata base_cpu_spec = { .cpu_name = NULL, .cpu_features = CPU_FTRS_DT_CPU_BASE,@@ -1069,6 +1067,7 @@ static int __init count_cpufeatures_subnodes(unsigned long node, static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char *uname, int depth, void *data) { + static char dt_cpu_name[64]; const __be32 *prop; int count, i; u32 isa;@@ -1106,10 +1105,8 @@ static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char } prop = of_get_flat_dt_prop(node, "display-name", NULL); - if (prop && strlen((char *)prop) != 0) { - strscpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name)); + if (prop && strscpy(dt_cpu_name, (char *)prop) != 0)
That is different code. The old code only did the copy if the new string was non-empty. So you want to replace the strlen() with *(char *)prop != 0. Checks for strlen() == 0 are silly (but surprisingly common). A search might show up this gem: str[strlen(str)] = 0; -- David
cur_cpu_spec->cpu_name = dt_cpu_name; - } cpufeatures_setup_finished();