From 0b0cae7119a0ec9449d7261b5e672a5fed765068 Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (Microsoft)" Date: Tue, 3 Jun 2025 14:14:43 +0300 Subject: x86/its: move its_pages array to struct mod_arch_specific The of pages with ITS thunks allocated for modules are tracked by an array in 'struct module'. Since this is very architecture specific data structure, move it to 'struct mod_arch_specific'. No functional changes. Fixes: 872df34d7c51 ("x86/its: Use dynamic thunks for indirect branches") Suggested-by: Peter Zijlstra (Intel) Signed-off-by: Mike Rapoport (Microsoft) Signed-off-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20250603111446.2609381-4-rppt@kernel.org --- include/linux/module.h | 5 ----- 1 file changed, 5 deletions(-) (limited to 'include') diff --git a/include/linux/module.h b/include/linux/module.h index 92e1420fccdf..5faa1fb1f4b4 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -586,11 +586,6 @@ struct module { atomic_t refcnt; #endif -#ifdef CONFIG_MITIGATION_ITS - int its_num_pages; - void **its_page_array; -#endif - #ifdef CONFIG_CONSTRUCTORS /* Constructor functions. */ ctor_fn_t *ctors; -- cgit v1.3 From 7cd9a11dd0c3d1dd225795ed1b5b53132888e7b5 Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (Microsoft)" Date: Tue, 3 Jun 2025 14:14:45 +0300 Subject: Revert "mm/execmem: Unify early execmem_cache behaviour" The commit d6d1e3e6580c ("mm/execmem: Unify early execmem_cache behaviour") changed early behaviour of execemem ROX cache to allow its usage in early x86 code that allocates text pages when CONFIG_MITGATION_ITS is enabled. The permission management of the pages allocated from execmem for ITS mitigation is now completely contained in arch/x86/kernel/alternatives.c and therefore there is no need to special case early allocations in execmem. This reverts commit d6d1e3e6580ca35071ad474381f053cbf1fb6414. Signed-off-by: Mike Rapoport (Microsoft) Signed-off-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20250603111446.2609381-6-rppt@kernel.org --- arch/x86/mm/init_32.c | 3 --- arch/x86/mm/init_64.c | 3 --- include/linux/execmem.h | 8 +------- mm/execmem.c | 40 +++------------------------------------- 4 files changed, 4 insertions(+), 50 deletions(-) (limited to 'include') diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 607d6a2e66e2..8a34fff6ab2b 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -30,7 +30,6 @@ #include #include #include -#include #include #include @@ -749,8 +748,6 @@ void mark_rodata_ro(void) pr_info("Write protecting kernel text and read-only data: %luk\n", size >> 10); - execmem_cache_make_ro(); - kernel_set_to_readonly = 1; #ifdef CONFIG_CPA_DEBUG diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index ee66fae9ebcc..fdb6cab524f0 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -34,7 +34,6 @@ #include #include #include -#include #include #include @@ -1392,8 +1391,6 @@ void mark_rodata_ro(void) (end - start) >> 10); set_memory_ro(start, (end - start) >> PAGE_SHIFT); - execmem_cache_make_ro(); - kernel_set_to_readonly = 1; /* diff --git a/include/linux/execmem.h b/include/linux/execmem.h index ca42d5e46ccc..3be35680a54f 100644 --- a/include/linux/execmem.h +++ b/include/linux/execmem.h @@ -54,7 +54,7 @@ enum execmem_range_flags { EXECMEM_ROX_CACHE = (1 << 1), }; -#if defined(CONFIG_ARCH_HAS_EXECMEM_ROX) && defined(CONFIG_EXECMEM) +#ifdef CONFIG_ARCH_HAS_EXECMEM_ROX /** * execmem_fill_trapping_insns - set memory to contain instructions that * will trap @@ -94,15 +94,9 @@ int execmem_make_temp_rw(void *ptr, size_t size); * Return: 0 on success or negative error code on failure. */ int execmem_restore_rox(void *ptr, size_t size); - -/* - * Called from mark_readonly(), where the system transitions to ROX. - */ -void execmem_cache_make_ro(void); #else static inline int execmem_make_temp_rw(void *ptr, size_t size) { return 0; } static inline int execmem_restore_rox(void *ptr, size_t size) { return 0; } -static inline void execmem_cache_make_ro(void) { } #endif /** diff --git a/mm/execmem.c b/mm/execmem.c index 9720ac2dfa41..2b683e7d864d 100644 --- a/mm/execmem.c +++ b/mm/execmem.c @@ -254,34 +254,6 @@ out_unlock: return ptr; } -static bool execmem_cache_rox = false; - -void execmem_cache_make_ro(void) -{ - struct maple_tree *free_areas = &execmem_cache.free_areas; - struct maple_tree *busy_areas = &execmem_cache.busy_areas; - MA_STATE(mas_free, free_areas, 0, ULONG_MAX); - MA_STATE(mas_busy, busy_areas, 0, ULONG_MAX); - struct mutex *mutex = &execmem_cache.mutex; - void *area; - - execmem_cache_rox = true; - - mutex_lock(mutex); - - mas_for_each(&mas_free, area, ULONG_MAX) { - unsigned long pages = mas_range_len(&mas_free) >> PAGE_SHIFT; - set_memory_ro(mas_free.index, pages); - } - - mas_for_each(&mas_busy, area, ULONG_MAX) { - unsigned long pages = mas_range_len(&mas_busy) >> PAGE_SHIFT; - set_memory_ro(mas_busy.index, pages); - } - - mutex_unlock(mutex); -} - static int execmem_cache_populate(struct execmem_range *range, size_t size) { unsigned long vm_flags = VM_ALLOW_HUGE_VMAP; @@ -302,15 +274,9 @@ static int execmem_cache_populate(struct execmem_range *range, size_t size) /* fill memory with instructions that will trap */ execmem_fill_trapping_insns(p, alloc_size, /* writable = */ true); - if (execmem_cache_rox) { - err = set_memory_rox((unsigned long)p, vm->nr_pages); - if (err) - goto err_free_mem; - } else { - err = set_memory_x((unsigned long)p, vm->nr_pages); - if (err) - goto err_free_mem; - } + err = set_memory_rox((unsigned long)p, vm->nr_pages); + if (err) + goto err_free_mem; err = execmem_cache_add(p, alloc_size); if (err) -- cgit v1.3