From 84355caa271a0eab2d1b55ff73aa8aa3e4627661 Mon Sep 17 00:00:00 2001 From: Thorsten Blum Date: Wed, 17 Dec 2025 12:02:13 +0100 Subject: [PATCH] mm/mm_init: replace simple_strtoul with kstrtobool in set_hashdist Use bool for 'hashdist' and replace simple_strtoul() with kstrtobool() for parsing the 'hashdist=' boot parameter. Unlike simple_strtoul(), which returns an unsigned long, kstrtobool() converts the string directly to bool and avoids implicit casting. Check the return value of kstrtobool() and reject invalid values. This adds error handling while preserving behavior for existing values, and removes use of the deprecated simple_strtoul() helper. The current code silently sets 'hashdist = 0' if parsing fails, instead of leaving the default value (HASHDIST_DEFAULT) unchanged. Additionally, kstrtobool() accepts common boolean strings such as "on" and "off". Link: https://lkml.kernel.org/r/20251217110214.50807-1-thorsten.blum@linux.dev Signed-off-by: Thorsten Blum Reviewed-by: Matthew Wilcox (Oracle) Reviewed-by: Mike Rapoport (Microsoft) Signed-off-by: Andrew Morton --- include/linux/memblock.h | 4 ++-- mm/mm_init.c | 9 +++------ 2 files changed, 5 insertions(+), 8 deletions(-) diff --git a/include/linux/memblock.h b/include/linux/memblock.h index 221118b5a16e1..6ec5e9ac06992 100644 --- a/include/linux/memblock.h +++ b/include/linux/memblock.h @@ -598,9 +598,9 @@ extern void *alloc_large_system_hash(const char *tablename, */ #ifdef CONFIG_NUMA #define HASHDIST_DEFAULT IS_ENABLED(CONFIG_64BIT) -extern int hashdist; /* Distribute hashes across NUMA nodes? */ +extern bool hashdist; /* Distribute hashes across NUMA nodes? */ #else -#define hashdist (0) +#define hashdist (false) #endif #ifdef CONFIG_MEMTEST diff --git a/mm/mm_init.c b/mm/mm_init.c index fc2a6f1e518f1..d86248566a56b 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -646,21 +646,18 @@ int __meminit early_pfn_to_nid(unsigned long pfn) return nid; } -int hashdist = HASHDIST_DEFAULT; +bool hashdist = HASHDIST_DEFAULT; static int __init set_hashdist(char *str) { - if (!str) - return 0; - hashdist = simple_strtoul(str, &str, 0); - return 1; + return kstrtobool(str, &hashdist) == 0; } __setup("hashdist=", set_hashdist); static inline void fixup_hashdist(void) { if (num_node_state(N_MEMORY) == 1) - hashdist = 0; + hashdist = false; } #else static inline void fixup_hashdist(void) {} -- 2.47.3