[PATCH v4 09/35] kmsan: Expose kmsan_get_metadata()
From: Ilya Leoshkevich <iii@linux.ibm.com>
Date: 2024-06-13 15:40:16
Also in:
linux-mm, linux-s390, lkml
Subsystem:
kmsan, memory management, the rest · Maintainers:
Alexander Potapenko, Andrew Morton, Linus Torvalds
Each s390 CPU has lowcore pages associated with it. Each CPU sees its own lowcore at virtual address 0 through a hardware mechanism called prefixing. Additionally, all lowcores are mapped to non-0 virtual addresses stored in the lowcore_ptr[] array. When lowcore is accessed through virtual address 0, one needs to resolve metadata for lowcore_ptr[raw_smp_processor_id()]. Expose kmsan_get_metadata() to make it possible to do this from the arch code. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> --- include/linux/kmsan.h | 9 +++++++++ mm/kmsan/instrumentation.c | 1 + mm/kmsan/kmsan.h | 1 - 3 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/include/linux/kmsan.h b/include/linux/kmsan.h
index e0c23a32cdf0..fe6c2212bdb1 100644
--- a/include/linux/kmsan.h
+++ b/include/linux/kmsan.h@@ -230,6 +230,15 @@ void kmsan_handle_urb(const struct urb *urb, bool is_out); */ void kmsan_unpoison_entry_regs(const struct pt_regs *regs); +/** + * kmsan_get_metadata() - Return a pointer to KMSAN shadow or origins. + * @addr: kernel address. + * @is_origin: whether to return origins or shadow. + * + * Return NULL if metadata cannot be found. + */ +void *kmsan_get_metadata(void *addr, bool is_origin); + #else static inline void kmsan_init_shadow(void)
diff --git a/mm/kmsan/instrumentation.c b/mm/kmsan/instrumentation.c
index 8a1bbbc723ab..94b49fac9d8b 100644
--- a/mm/kmsan/instrumentation.c
+++ b/mm/kmsan/instrumentation.c@@ -14,6 +14,7 @@ #include "kmsan.h" #include <linux/gfp.h> +#include <linux/kmsan.h> #include <linux/kmsan_string.h> #include <linux/mm.h> #include <linux/uaccess.h>
diff --git a/mm/kmsan/kmsan.h b/mm/kmsan/kmsan.h
index adf443bcffe8..34b83c301d57 100644
--- a/mm/kmsan/kmsan.h
+++ b/mm/kmsan/kmsan.h@@ -66,7 +66,6 @@ struct shadow_origin_ptr { struct shadow_origin_ptr kmsan_get_shadow_origin_ptr(void *addr, u64 size, bool store); -void *kmsan_get_metadata(void *addr, bool is_origin); void __init kmsan_init_alloc_meta_for_range(void *start, void *end); enum kmsan_bug_reason {
--
2.45.1