+ s390-mm-define-kmsan-metadata-for-vmalloc-and-modules.patch added to mm-unstable branch

0 views
Skip to first unread message

Andrew Morton

unread,
Jun 19, 2024, 8:59:21 PMJun 19
to mm-co...@vger.kernel.org, vba...@suse.cz, sv...@linux.ibm.com, ros...@goodmis.org, roman.g...@linux.dev, rien...@google.com, pen...@kernel.org, mhir...@kernel.org, mark.r...@arm.com, kasa...@googlegroups.com, iamjoon...@lge.com, h...@linux.ibm.com, g...@linux.ibm.com, gli...@google.com, el...@google.com, dvy...@google.com, c...@linux.com, bornt...@linux.ibm.com, agor...@linux.ibm.com, 42.h...@gmail.com, i...@linux.ibm.com, ak...@linux-foundation.org

The patch titled
Subject: s390/mm: define KMSAN metadata for vmalloc and modules
has been added to the -mm mm-unstable branch. Its filename is
s390-mm-define-kmsan-metadata-for-vmalloc-and-modules.patch

This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/s390-mm-define-kmsan-metadata-for-vmalloc-and-modules.patch

This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

------------------------------------------------------
From: Ilya Leoshkevich <i...@linux.ibm.com>
Subject: s390/mm: define KMSAN metadata for vmalloc and modules
Date: Wed, 19 Jun 2024 17:44:05 +0200

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/20240619154530...@linux.ibm.com
Signed-off-by: Ilya Leoshkevich <i...@linux.ibm.com>
Reviewed-by: Alexander Potapenko <gli...@google.com>
Acked-by: Alexander Gordeev <agor...@linux.ibm.com>
Acked-by: Heiko Carstens <h...@linux.ibm.com>
Cc: Christian Borntraeger <bornt...@linux.ibm.com>
Cc: Christoph Lameter <c...@linux.com>
Cc: David Rientjes <rien...@google.com>
Cc: Dmitry Vyukov <dvy...@google.com>
Cc: Hyeonggon Yoo <42.h...@gmail.com>
Cc: Joonsoo Kim <iamjoon...@lge.com>
Cc: <kasa...@googlegroups.com>
Cc: Marco Elver <el...@google.com>
Cc: Mark Rutland <mark.r...@arm.com>
Cc: Masami Hiramatsu (Google) <mhir...@kernel.org>
Cc: Pekka Enberg <pen...@kernel.org>
Cc: Roman Gushchin <roman.g...@linux.dev>
Cc: Steven Rostedt (Google) <ros...@goodmis.org>
Cc: Sven Schnelle <sv...@linux.ibm.com>
Cc: Vasily Gorbik <g...@linux.ibm.com>
Cc: Vlastimil Babka <vba...@suse.cz>
Signed-off-by: Andrew Morton <ak...@linux-foundation.org>
---

arch/s390/boot/startup.c | 7 +++++++
arch/s390/include/asm/pgtable.h | 8 ++++++++
2 files changed, 15 insertions(+)

--- a/arch/s390/boot/startup.c~s390-mm-define-kmsan-metadata-for-vmalloc-and-modules
+++ a/arch/s390/boot/startup.c
@@ -301,11 +301,18 @@ static unsigned long setup_kernel_memory
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);
--- a/arch/s390/include/asm/pgtable.h~s390-mm-define-kmsan-metadata-for-vmalloc-and-modules
+++ a/arch/s390/include/asm/pgtable.h
@@ -107,6 +107,14 @@ static inline int is_module_addr(void *a
return 1;
}

+#ifdef CONFIG_KMSAN
+#define KMSAN_VMALLOC_SIZE (VMALLOC_END - VMALLOC_START)
+#define KMSAN_VMALLOC_SHADOW_START VMALLOC_END
+#define KMSAN_VMALLOC_ORIGIN_START (KMSAN_VMALLOC_SHADOW_START + KMSAN_VMALLOC_SIZE)
+#define KMSAN_MODULES_SHADOW_START (KMSAN_VMALLOC_ORIGIN_START + KMSAN_VMALLOC_SIZE)
+#define KMSAN_MODULES_ORIGIN_START (KMSAN_MODULES_SHADOW_START + MODULES_LEN)
+#endif
+
#ifdef CONFIG_RANDOMIZE_BASE
#define KASLR_LEN (1UL << 31)
#else
_

Patches currently in -mm which might be from i...@linux.ibm.com are

ftrace-unpoison-ftrace_regs-in-ftrace_ops_list_func.patch
kmsan-make-the-tests-compatible-with-kmsanpanic=1.patch
kmsan-disable-kmsan-when-deferred_struct_page_init-is-enabled.patch
kmsan-increase-the-maximum-store-size-to-4096.patch
kmsan-fix-is_bad_asm_addr-on-arches-with-overlapping-address-spaces.patch
kmsan-fix-kmsan_copy_to_user-on-arches-with-overlapping-address-spaces.patch
kmsan-remove-a-useless-assignment-from-kmsan_vmap_pages_range_noflush.patch
kmsan-remove-an-x86-specific-include-from-kmsanh.patch
kmsan-expose-kmsan_get_metadata.patch
kmsan-export-panic_on_kmsan.patch
kmsan-allow-disabling-kmsan-checks-for-the-current-task.patch
kmsan-introduce-memset_no_sanitize_memory.patch
kmsan-support-slab_poison.patch
kmsan-use-align_down-in-kmsan_get_metadata.patch
kmsan-do-not-round-up-pg_data_t-size.patch
mm-slub-let-kmsan-access-metadata.patch
mm-slub-disable-kmsan-when-checking-the-padding-bytes.patch
mm-kfence-disable-kmsan-when-checking-the-canary.patch
lib-zlib-unpoison-dfltcc-output-buffers.patch
kmsan-accept-ranges-starting-with-0-on-s390.patch
s390-boot-turn-off-kmsan.patch
s390-use-a-larger-stack-for-kmsan.patch
s390-boot-add-the-kmsan-runtime-stub.patch
s390-checksum-add-a-kmsan-check.patch
s390-cpacf-unpoison-the-results-of-cpacf_trng.patch
s390-cpumf-unpoison-stcctm-output-buffer.patch
s390-diag-unpoison-diag224-output-buffer.patch
s390-ftrace-unpoison-ftrace_regs-in-kprobe_ftrace_handler.patch
s390-irqflags-do-not-instrument-arch_local_irq_-with-kmsan.patch
s390-mm-define-kmsan-metadata-for-vmalloc-and-modules.patch
s390-string-add-kmsan-support.patch
s390-traps-unpoison-the-kernel_stack_overflows-pt_regs.patch
s390-uaccess-add-kmsan-support-to-put_user-and-get_user.patch
s390-uaccess-add-the-missing-linux-instrumentedh-include.patch
s390-unwind-disable-kmsan-checks.patch
s390-kmsan-implement-the-architecture-specific-functions.patch
kmsan-enable-on-s390.patch

Reply all
Reply to author
Forward
0 new messages