From 6b1709d4b7fce27c6c79fc78c17c458f9848a4d8 Mon Sep 17 00:00:00 2001 From: Ilya Leoshkevich Date: Fri, 21 Jun 2024 13:34:53 +0200 Subject: kmsan: expose kmsan_get_metadata() 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. Link: https://lkml.kernel.org/r/20240621113706.315500-10-iii@linux.ibm.com Signed-off-by: Ilya Leoshkevich Reviewed-by: Alexander Potapenko Cc: Alexander Gordeev Cc: Christian Borntraeger Cc: Christoph Lameter Cc: David Rientjes Cc: Dmitry Vyukov Cc: Heiko Carstens Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Joonsoo Kim Cc: Cc: Marco Elver Cc: Mark Rutland Cc: Masami Hiramatsu (Google) Cc: Pekka Enberg Cc: Roman Gushchin Cc: Steven Rostedt (Google) Cc: Sven Schnelle Cc: Vasily Gorbik Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- include/linux/kmsan.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/linux') 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) -- cgit v1.2.3