summaryrefslogtreecommitdiff
path: root/mm
diff options
context:
space:
mode:
authorMike Rapoport (Microsoft) <rppt@kernel.org>2025-06-03 14:14:45 +0300
committerPeter Zijlstra <peterz@infradead.org>2025-06-11 12:20:52 +0300
commit7cd9a11dd0c3d1dd225795ed1b5b53132888e7b5 (patch)
tree50f0c07dc45da5f5b73f4475ec55a810bcc9e44b /mm
parenta82b26451de126a5ae130361081986bc459afe9b (diff)
downloadlinux-7cd9a11dd0c3d1dd225795ed1b5b53132888e7b5.tar.xz
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) <rppt@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20250603111446.2609381-6-rppt@kernel.org
Diffstat (limited to 'mm')
-rw-r--r--mm/execmem.c40
1 files changed, 3 insertions, 37 deletions
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)