From: Ilya Leoshkevich Date: Fri, 21 Jun 2024 11:35:15 +0000 (+0200) Subject: s390/mm: define KMSAN metadata for vmalloc and modules X-Git-Tag: v6.11-rc1~85^2~176 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=65ca73f9fb36740b0788620c783245fdb22e1535;p=thirdparty%2Flinux.git s390/mm: define KMSAN metadata for vmalloc and modules The pages for the KMSAN metadata associated with most kernel mappings are taken from memblock by the common code. However, vmalloc and module metadata needs to be defined by the architectures. Be a little bit more careful than x86: allocate exactly MODULES_LEN for the module shadow and origins, and then take 2/3 of vmalloc for the vmalloc shadow and origins. This ensures that users passing small vmalloc= values on the command line do not cause module metadata collisions. Link: https://lkml.kernel.org/r/20240621113706.315500-32-iii@linux.ibm.com Signed-off-by: Ilya Leoshkevich Reviewed-by: Alexander Potapenko Acked-by: Alexander Gordeev Acked-by: Heiko Carstens Cc: Christian Borntraeger Cc: Christoph Lameter Cc: David Rientjes Cc: Dmitry Vyukov 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 --- diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c index 5a36d5538dae8..4ff3126320f11 100644 --- a/arch/s390/boot/startup.c +++ b/arch/s390/boot/startup.c @@ -304,11 +304,18 @@ static unsigned long setup_kernel_memory_layout(unsigned long kernel_size) MODULES_END = round_down(kernel_start, _SEGMENT_SIZE); MODULES_VADDR = MODULES_END - MODULES_LEN; VMALLOC_END = MODULES_VADDR; + if (IS_ENABLED(CONFIG_KMSAN)) + VMALLOC_END -= MODULES_LEN * 2; /* allow vmalloc area to occupy up to about 1/2 of the rest virtual space left */ vsize = (VMALLOC_END - FIXMAP_SIZE) / 2; vsize = round_down(vsize, _SEGMENT_SIZE); vmalloc_size = min(vmalloc_size, vsize); + if (IS_ENABLED(CONFIG_KMSAN)) { + /* take 2/3 of vmalloc area for KMSAN shadow and origins */ + vmalloc_size = round_down(vmalloc_size / 3, _SEGMENT_SIZE); + VMALLOC_END -= vmalloc_size * 2; + } VMALLOC_START = VMALLOC_END - vmalloc_size; __memcpy_real_area = round_down(VMALLOC_START - MEMCPY_REAL_SIZE, PAGE_SIZE); diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 70b6ee557eb22..fb6870384b979 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -107,6 +107,18 @@ static inline int is_module_addr(void *addr) return 1; } +#ifdef CONFIG_KMSAN +#define KMSAN_VMALLOC_SIZE (VMALLOC_END - VMALLOC_START) +#define KMSAN_VMALLOC_SHADOW_START VMALLOC_END +#define KMSAN_VMALLOC_SHADOW_END (KMSAN_VMALLOC_SHADOW_START + KMSAN_VMALLOC_SIZE) +#define KMSAN_VMALLOC_ORIGIN_START KMSAN_VMALLOC_SHADOW_END +#define KMSAN_VMALLOC_ORIGIN_END (KMSAN_VMALLOC_ORIGIN_START + KMSAN_VMALLOC_SIZE) +#define KMSAN_MODULES_SHADOW_START KMSAN_VMALLOC_ORIGIN_END +#define KMSAN_MODULES_SHADOW_END (KMSAN_MODULES_SHADOW_START + MODULES_LEN) +#define KMSAN_MODULES_ORIGIN_START KMSAN_MODULES_SHADOW_END +#define KMSAN_MODULES_ORIGIN_END (KMSAN_MODULES_ORIGIN_START + MODULES_LEN) +#endif + #ifdef CONFIG_RANDOMIZE_BASE #define KASLR_LEN (1UL << 31) #else