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2021-04-30mm, page_alloc: avoid page_to_pfn() in move_freepages()Kefeng Wang1-15/+13
The start_pfn and end_pfn are already available in move_freepages_block(), there is no need to go back and forth between page and pfn in move_freepages and move_freepages_block, and pfn_valid_within() should validate pfn first before touching the page. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kefeng Wang <[email protected]> Signed-off-by: Liu Shixin <[email protected]> Reviewed-by: Matthew Wilcox (Oracle) <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Cc: Stephen Rothwell <[email protected]> Cc: Michal Hocko <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/Kconfig: remove default DISCONTIGMEM_MANUALGeert Uytterhoeven1-1/+0
Commit 214496cb18700fd7 ("ia64: make SPARSEMEM default and disable DISCONTIGMEM") removed the last enabler of ARCH_DISCONTIGMEM_DEFAULT, hence the memory model can no longer default to DISCONTIGMEM_MANUAL. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Geert Uytterhoeven <[email protected]> Reviewed-by: Mike Rapoport <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm: page_alloc: dump migrate-failed pagesMinchan Kim1-0/+22
Currently, debugging CMA allocation failures is quite limited. The most common source of these failures seems to be page migration which doesn't provide any useful information on the reason of the failure by itself. alloc_contig_range can report those failures as it holds a list of migrate-failed pages. The information logged by dump_page() has already proven helpful for debugging allocation issues, like identifying long-term pinnings on ZONE_MOVABLE or MIGRATE_CMA. Let's use the dynamic debugging infrastructure, such that we avoid flooding the logs and creating a lot of noise on frequent alloc_contig_range() calls. This information is helpful for debugging only. There are two ifdefery conditions to support common dyndbg options: - CONFIG_DYNAMIC_DEBUG_CORE && DYNAMIC_DEBUG_MODULE It aims for supporting the feature with only specific file with adding ccflags. - CONFIG_DYNAMIC_DEBUG It aims for supporting the feature with system wide globally. A simple example to enable the feature: Admin could enable the dump like this(by default, disabled) echo "func alloc_contig_dump_pages +p" > control Admin could disable it. echo "func alloc_contig_dump_pages =_" > control Detail goes Documentation/admin-guide/dynamic-debug-howto.rst A concern is utility functions in dump_page use inconsistent loglevels. In the future, we might want to make the loglevels used inside dump_page() consistent and eventually rework the way we log the information here. See [1]. [1] https://lore.kernel.org/linux-mm/[email protected]/ Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Minchan Kim <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Cc: John Dias <[email protected]> Cc: Michal Hocko <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Jason Baron <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/mempolicy: fix mpol_misplaced kernel-docMatthew Wilcox (Oracle)2-7/+5
Sphinx interprets the Return section as a list and complains about it. Turn it into a sentence and move it to the end of the kernel-doc to fit the kernel-doc style. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Acked-by: Mike Rapoport <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Cc: Michal Hocko <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/mempolicy: rewrite alloc_pages_vma documentationMatthew Wilcox (Oracle)1-21/+13
The current formatting doesn't quite work with kernel-doc. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Acked-by: Mike Rapoport <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Cc: Michal Hocko <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/mempolicy: rewrite alloc_pages documentationMatthew Wilcox (Oracle)1-11/+10
Document alloc_pages() for both NUMA and non-NUMA cases as kernel-doc doesn't care. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Acked-by: Mike Rapoport <[email protected]> Acked-by: Michal Hocko <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/mempolicy: rename alloc_pages_current to alloc_pagesMatthew Wilcox (Oracle)2-10/+4
When CONFIG_NUMA is enabled, alloc_pages() is a wrapper around alloc_pages_current(). This is pointless, just implement alloc_pages() directly. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/page_alloc: combine __alloc_pages and __alloc_pages_nodemaskMatthew Wilcox (Oracle)7-21/+13
There are only two callers of __alloc_pages() so prune the thicket of alloc_page variants by combining the two functions together. Current callers of __alloc_pages() simply add an extra 'NULL' parameter and current callers of __alloc_pages_nodemask() call __alloc_pages() instead. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/page_alloc: rename gfp_mask to gfpMatthew Wilcox (Oracle)1-9/+9
Shorten some overly-long lines by renaming this identifier. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/page_alloc: rename alloc_mask to alloc_gfpMatthew Wilcox (Oracle)1-9/+10
Patch series "Rationalise __alloc_pages wrappers", v3. I was poking around the __alloc_pages variants trying to understand why they each exist, and couldn't really find a good justification for keeping __alloc_pages and __alloc_pages_nodemask as separate functions. That led to getting rid of alloc_pages_current() and then I noticed the documentation was bad, and then I noticed the mempolicy documentation wasn't included. Anyway, this is all cleanups & doc fixes. This patch (of 7): We have two masks involved -- the nodemask and the gfp mask, so alloc_mask is an unclear name. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30include/linux/page-flags-layout.h: cleanupsYu Zhao2-37/+29
Tidy things up and delete comments stating the obvious with typos or making no sense. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Yu Zhao <[email protected]> Cc: Matthew Wilcox <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30include/linux/page-flags-layout.h: correctly determine LAST_CPUPID_WIDTHYu Zhao1-1/+1
The naming convention used in include/linux/page-flags-layout.h: *_SHIFT: the number of bits trying to allocate *_WIDTH: the number of bits successfully allocated So when it comes to LAST_CPUPID_WIDTH, we need to check whether all previous *_WIDTH and LAST_CPUPID_SHIFT can fit into page flags. This means we need to use NODES_WIDTH, not NODES_SHIFT. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Yu Zhao <[email protected]> Cc: Matthew Wilcox <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm: remove lru_add_drain_all in alloc_contig_rangeMinchan Kim1-2/+0
__alloc_contig_migrate_range already has lru_add_drain_all call via migrate_prep. It's necessary to move LRU taget pages into LRU list to be able to isolated. However, lru_add_drain_all call after __alloc_contig_migrate_range is pointless since it has changed source page freeing from putback_lru_pages to put_page[1]. This patch removes it. [1] c6c919eb90e0, ("mm: use put_page() to free page instead of putback_lru_page()" Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Minchan Kim <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Acked-by: Michal Hocko <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/page_alloc: drop pr_info_ratelimited() in alloc_contig_range()David Hildenbrand1-2/+0
The information that some PFNs are busy is: a) not helpful for ordinary users: we don't even know *who* called alloc_contig_range(). This is certainly not worth a pr_info.*(). b) not really helpful for debugging: we don't have any details *why* these PFNs are busy, and that is what we usually care about. c) not complete: there are other cases where we fail alloc_contig_range() using different paths that are not getting recorded. For example, we reach this path once we succeeded in isolating pageblocks, but failed to migrate some pages - which can happen easily on ZONE_NORMAL (i.e., has_unmovable_pages() is racy) but also on ZONE_MOVABLE i.e., we would have to retry longer to migrate). For example via virtio-mem when unplugging memory, we can create quite some noise (especially with ZONE_NORMAL) that is not of interest to users - it's expected that some allocations may fail as memory is busy. Let's just drop that pr_info_ratelimit() and rather implement a dynamic debugging mechanism in the future that can give us a better reason why alloc_contig_range() failed on specific pages. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Reviewed-by: Zi Yan <[email protected]> Acked-by: Michal Hocko <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Acked-by: Minchan Kim <[email protected]> Cc: Vlastimil Babka <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm: move mem_init_print_info() into mm_init()Kefeng Wang30-42/+7
mem_init_print_info() is called in mem_init() on each architecture, and pass NULL argument, so using void argument and move it into mm_init(). Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kefeng Wang <[email protected]> Acked-by: Dave Hansen <[email protected]> [x86] Reviewed-by: Christophe Leroy <[email protected]> [powerpc] Acked-by: David Hildenbrand <[email protected]> Tested-by: Anatoly Pugachev <[email protected]> [sparc64] Acked-by: Russell King <[email protected]> [arm] Acked-by: Mike Rapoport <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Richard Henderson <[email protected]> Cc: Guo Ren <[email protected]> Cc: Yoshinori Sato <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Jonas Bonn <[email protected]> Cc: Palmer Dabbelt <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: "Peter Zijlstra" <[email protected]> Cc: Ingo Molnar <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30irq_work: record irq_work_queue() call stackZqiang1-1/+6
Add the irq_work_queue() call stack into the KASAN auxiliary stack in order to improve KASAN reports. this will let us know where the irq work be queued. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Zqiang <[email protected]> Reviewed-by: Dmitry Vyukov <[email protected]> Acked-by: Andrey Konovalov <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Matthias Brugger <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Walter Wu <[email protected]> Cc: Frederic Weisbecker <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: detect false-positives in testsAndrey Konovalov1-26/+29
Currently, KASAN-KUnit tests can check that a particular annotated part of code causes a KASAN report. However, they do not check that no unwanted reports happen between the annotated parts. This patch implements these checks. It is done by setting report_data.report_found to false in kasan_test_init() and at the end of KUNIT_EXPECT_KASAN_FAIL() and then checking that it remains false at the beginning of KUNIT_EXPECT_KASAN_FAIL() and in kasan_test_exit(). kunit_add_named_resource() call is moved to kasan_test_init(), and the value of fail_data.report_expected is kept as false in between KUNIT_EXPECT_KASAN_FAIL() annotations for consistency. Link: https://lkml.kernel.org/r/48079c52cc329fbc52f4386996598d58022fb872.1617207873.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Andrey Ryabinin <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: record task_work_add() call stackWalter Wu2-1/+4
Why record task_work_add() call stack? Syzbot reports many use-after-free issues for task_work, see [1]. After seeing the free stack and the current auxiliary stack, we think they are useless, we don't know where the work was registered. This work may be the free call stack, so we miss the root cause and don't solve the use-after-free. Add the task_work_add() call stack into the KASAN auxiliary stack in order to improve KASAN reports. It helps programmers solve use-after-free issues. [1]: https://groups.google.com/g/syzkaller-bugs/search?q=kasan%20use-after-free%20task_work_run Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Walter Wu <[email protected]> Suggested-by: Dmitry Vyukov <[email protected]> Reviewed-by: Dmitry Vyukov <[email protected]> Reviewed-by: Jens Axboe <[email protected]> Acked-by: Oleg Nesterov <[email protected]> Acked-by: Andrey Konovalov <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Matthias Brugger <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: docs: update tests sectionAndrey Konovalov1-17/+15
Update the "Tests" section in KASAN documentation: - Add an introductory sentence. - Add proper indentation for the list of ways to run KUnit tests. - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/fb08845e25c8847ffda271fa19cda2621c04a65b.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: docs: update ignoring accesses sectionAndrey Konovalov1-4/+30
Update the "Ignoring accesses" section in KASAN documentation: - Mention __no_sanitize_address/noinstr. - Mention kasan_disable/enable_current(). - Mention kasan_reset_tag()/page_kasan_tag_reset(). - Readability and punctuation clean-ups. Link: https://lkml.kernel.org/r/4531ba5f3eca61f6aade863c136778cc8c807a64.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: docs: update shadow memory sectionAndrey Konovalov1-17/+14
Update the "Shadow memory" section in KASAN documentation: - Rearrange the introduction paragraph do it doesn't give a "KASAN has an issue" impression. - Update the list of architectures with vmalloc support. - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/00f8c38b0fd5290a3f4dced04eaba41383e67e14.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: docs: update HW_TAGS implementation details sectionAndrey Konovalov1-13/+13
Update the "Implementation details" section for HW_TAGS KASAN: - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/ee2caf4c138cc1fd239822c2abefd5af6c057744.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: docs: update SW_TAGS implementation details sectionAndrey Konovalov1-20/+19
Update the "Implementation details" section for SW_TAGS KASAN: - Clarify the introduction sentence. - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/69b9b2e49d8cf789358fa24558be3fc0ce4ee32c.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: docs: update GENERIC implementation details sectionAndrey Konovalov1-14/+13
Update the "Implementation details" section for generic KASAN: - Don't mention kmemcheck, it's not present in the kernel anymore. - Don't mention GCC as the only supported compiler. - Update kasan_mem_to_shadow() definition to match actual code. - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/f2f35fdab701f8c709f63d328f98aec2982c8acc.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: docs: update boot parameters sectionAndrey Konovalov1-4/+10
Update the "Boot parameters" section in KASAN documentation: - Mention panic_on_warn. - Mention kasan_multi_shot and its interaction with panic_on_warn. - Clarify kasan.fault=panic interaction with panic_on_warn. - A readability clean-up. Link: https://lkml.kernel.org/r/01364952f15789948f0627d6733b5cdf5209f83a.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: docs: update error reports sectionAndrey Konovalov1-20/+26
Update the "Error reports" section in KASAN documentation: - Mention that bug titles are best-effort. - Move and reword the part about auxiliary stacks from "Implementation details". - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/3531e8fe6972cf39d1954e3643237b19eb21227e.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: docs: update usage sectionAndrey Konovalov1-12/+11
Update the "Usage" section in KASAN documentation: - Add inline code snippet markers. - Reword the part about stack traces for clarity. - Other minor clean-ups. Link: https://lkml.kernel.org/r/48427809cd4b8b5d6bc00926cbe87e2b5081df17.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: docs: update overview sectionAndrey Konovalov1-8/+19
Update the "Overview" section in KASAN documentation: - Outline main use cases for each mode. - Mention that HW_TAGS mode need compiler support too. - Move the part about SLUB/SLAB support from "Usage" to "Overview". - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/1486fba8514de3d7db2f47df2192db59228b0a7b.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: docs: clean up sectionsAndrey Konovalov1-27/+27
Update KASAN documentation: - Give some sections clearer names. - Remove unneeded subsections in the "Tests" section. - Move the "For developers" section and split into subsections. Link: https://lkml.kernel.org/r/c2bbb56eaea80ad484f0ee85bb71959a3a63f1d7.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan, mm: integrate slab init_on_free with HW_TAGSAndrey Konovalov4-33/+48
This change uses the previously added memory initialization feature of HW_TAGS KASAN routines for slab memory when init_on_free is enabled. With this change, memory initialization memset() is no longer called when both HW_TAGS KASAN and init_on_free are enabled. Instead, memory is initialized in KASAN runtime. For SLUB, the memory initialization memset() is moved into slab_free_hook() that currently directly follows the initialization loop. A new argument is added to slab_free_hook() that indicates whether to initialize the memory or not. To avoid discrepancies with which memory gets initialized that can be caused by future changes, both KASAN hook and initialization memset() are put together and a warning comment is added. Combining setting allocation tags with memory initialization improves HW_TAGS KASAN performance when init_on_free is enabled. Link: https://lkml.kernel.org/r/190fd15c1886654afdec0d19ebebd5ade665b601.1615296150.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Branislav Rankov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: David Rientjes <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Evgenii Stepanov <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Kevin Brodsky <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: Peter Collingbourne <[email protected]> Cc: Vincenzo Frascino <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan, mm: integrate slab init_on_alloc with HW_TAGSAndrey Konovalov5-41/+43
This change uses the previously added memory initialization feature of HW_TAGS KASAN routines for slab memory when init_on_alloc is enabled. With this change, memory initialization memset() is no longer called when both HW_TAGS KASAN and init_on_alloc are enabled. Instead, memory is initialized in KASAN runtime. The memory initialization memset() is moved into slab_post_alloc_hook() that currently directly follows the initialization loop. A new argument is added to slab_post_alloc_hook() that indicates whether to initialize the memory or not. To avoid discrepancies with which memory gets initialized that can be caused by future changes, both KASAN hook and initialization memset() are put together and a warning comment is added. Combining setting allocation tags with memory initialization improves HW_TAGS KASAN performance when init_on_alloc is enabled. Link: https://lkml.kernel.org/r/c1292aeb5d519da221ec74a0684a949b027d7720.1615296150.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Branislav Rankov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: David Rientjes <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Evgenii Stepanov <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Kevin Brodsky <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: Peter Collingbourne <[email protected]> Cc: Vincenzo Frascino <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan, mm: integrate page_alloc init with HW_TAGSAndrey Konovalov4-24/+59
This change uses the previously added memory initialization feature of HW_TAGS KASAN routines for page_alloc memory when init_on_alloc/free is enabled. With this change, kernel_init_free_pages() is no longer called when both HW_TAGS KASAN and init_on_alloc/free are enabled. Instead, memory is initialized in KASAN runtime. To avoid discrepancies with which memory gets initialized that can be caused by future changes, both KASAN and kernel_init_free_pages() hooks are put together and a warning comment is added. This patch changes the order in which memory initialization and page poisoning hooks are called. This doesn't lead to any side-effects, as whenever page poisoning is enabled, memory initialization gets disabled. Combining setting allocation tags with memory initialization improves HW_TAGS KASAN performance when init_on_alloc/free is enabled. [[email protected]: fix for "integrate page_alloc init with HW_TAGS"] Link: https://lkml.kernel.org/r/65b6028dea2e9a6e8e2cb779b5115c09457363fc.1617122211.git.andreyknvl@google.com Link: https://lkml.kernel.org/r/e77f0d5b1b20658ef0b8288625c74c2b3690e725.1615296150.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Tested-by: Vlastimil Babka <[email protected]> Reviewed-by: Sergei Trofimovich <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Branislav Rankov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: David Rientjes <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Evgenii Stepanov <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Kevin Brodsky <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: Peter Collingbourne <[email protected]> Cc: Vincenzo Frascino <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: init memory in kasan_(un)poison for HW_TAGSAndrey Konovalov6-34/+36
This change adds an argument to kasan_poison() and kasan_unpoison() that allows initializing memory along with setting the tags for HW_TAGS. Combining setting allocation tags with memory initialization will improve HW_TAGS KASAN performance when init_on_alloc/free is enabled. This change doesn't integrate memory initialization with KASAN, this is done is subsequent patches in this series. Link: https://lkml.kernel.org/r/3054314039fa64510947e674180d675cab1b4c41.1615296150.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Branislav Rankov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: David Rientjes <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Evgenii Stepanov <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Kevin Brodsky <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: Peter Collingbourne <[email protected]> Cc: Vincenzo Frascino <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30arm64: kasan: allow to init memory when setting tagsAndrey Konovalov3-20/+32
Patch series "kasan: integrate with init_on_alloc/free", v3. This patch series integrates HW_TAGS KASAN with init_on_alloc/free by initializing memory via the same arm64 instruction that sets memory tags. This is expected to improve HW_TAGS KASAN performance when init_on_alloc/free is enabled. The exact perfomance numbers are unknown as MTE-enabled hardware doesn't exist yet. This patch (of 5): This change adds an argument to mte_set_mem_tag_range() that allows to enable memory initialization when settinh the allocation tags. The implementation uses stzg instruction instead of stg when this argument indicates to initialize memory. Combining setting allocation tags with memory initialization will improve HW_TAGS KASAN performance when init_on_alloc/free is enabled. This change doesn't integrate memory initialization with KASAN, this is done is subsequent patches in this series. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/d04ae90cc36be3fe246ea8025e5085495681c3d7.1615296150.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Acked-by: Marco Elver <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: David Rientjes <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Will Deacon <[email protected]> Cc: Vincenzo Frascino <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Peter Collingbourne <[email protected]> Cc: Evgenii Stepanov <[email protected]> Cc: Branislav Rankov <[email protected]> Cc: Kevin Brodsky <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm, kasan: don't poison boot memory with tag-based modesAndrey Konovalov1-11/+34
During boot, all non-reserved memblock memory is exposed to page_alloc via memblock_free_pages->__free_pages_core(). This results in kasan_free_pages() being called, which poisons that memory. Poisoning all that memory lengthens boot time. The most noticeable effect is observed with the HW_TAGS mode. A boot-time impact may potentially also affect systems with large amount of RAM. This patch changes the tag-based modes to not poison the memory during the memblock->page_alloc transition. An exception is made for KASAN_GENERIC. Since it marks all new memory as accessible, not poisoning the memory released from memblock will lead to KASAN missing invalid boot-time accesses to that memory. With KASAN_SW_TAGS, as it uses the invalid 0xFE tag as the default tag for all memory, it won't miss bad boot-time accesses even if the poisoning of memblock memory is removed. With KASAN_HW_TAGS, the default memory tags values are unspecified. Therefore, if memblock poisoning is removed, this KASAN mode will miss the mentioned type of boot-time bugs with a 1/16 probability. This is taken as an acceptable trafe-off. Internally, the poisoning is removed as follows. __free_pages_core() is used when exposing fresh memory during system boot and when onlining memory during hotplug. This patch adds a new FPI_SKIP_KASAN_POISON flag and passes it to __free_pages_ok() through free_pages_prepare() from __free_pages_core(). If FPI_SKIP_KASAN_POISON is set, kasan_free_pages() is not called. All memory allocated normally when the boot is over keeps getting poisoned as usual. Link: https://lkml.kernel.org/r/a0570dc1e3a8f39a55aa343a1fc08cd5c2d4cad6.1613692950.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Catalin Marinas <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Will Deacon <[email protected]> Cc: Vincenzo Frascino <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Marco Elver <[email protected]> Cc: Peter Collingbourne <[email protected]> Cc: Evgenii Stepanov <[email protected]> Cc: Branislav Rankov <[email protected]> Cc: Kevin Brodsky <[email protected]> Cc: Christoph Hellwig <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: initialize shadow to TAG_INVALID for SW_TAGSAndrey Konovalov1-1/+2
Currently, KASAN_SW_TAGS uses 0xFF as the default tag value for unallocated memory. The underlying idea is that since that memory hasn't been allocated yet, it's only supposed to be dereferenced through a pointer with the native 0xFF tag. While this is a good idea in terms on consistency, practically it doesn't bring any benefit. Since the 0xFF pointer tag is a match-all tag, it doesn't matter what tag the accessed memory has. No accesses through 0xFF-tagged pointers are considered buggy by KASAN. This patch changes the default tag value for unallocated memory to 0xFE, which is the tag KASAN uses for inaccessible memory. This doesn't affect accesses through 0xFF-tagged pointer to this memory, but this allows KASAN to detect wild and large out-of-bounds invalid memory accesses through otherwise-tagged pointers. This is a prepatory patch for the next one, which changes the tag-based KASAN modes to not poison the boot memory. Link: https://lkml.kernel.org/r/c8e93571c18b3528aac5eb33ade213bf133d10ad.1613692950.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Branislav Rankov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Evgenii Stepanov <[email protected]> Cc: Kevin Brodsky <[email protected]> Cc: Marco Elver <[email protected]> Cc: Peter Collingbourne <[email protected]> Cc: Vincenzo Frascino <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30kasan: fix kasan_byte_accessible() to be consistent with actual checksPeter Collingbourne2-5/+8
We can sometimes end up with kasan_byte_accessible() being called on non-slab memory. For example ksize() and krealloc() may end up calling it on KFENCE allocated memory. In this case the memory will be tagged with KASAN_SHADOW_INIT, which a subsequent patch ("kasan: initialize shadow to TAG_INVALID for SW_TAGS") will set to the same value as KASAN_TAG_INVALID, causing kasan_byte_accessible() to fail when called on non-slab memory. This highlighted the fact that the check in kasan_byte_accessible() was inconsistent with checks as implemented for loads and stores (kasan_check_range() in SW tags mode and hardware-implemented checks in HW tags mode). kasan_check_range() does not have a check for KASAN_TAG_INVALID, and instead has a comparison against KASAN_SHADOW_START. In HW tags mode, we do not have either, but we do set TCR_EL1.TCMA which corresponds with the comparison against KASAN_TAG_KERNEL. Therefore, update kasan_byte_accessible() for both SW and HW tags modes to correspond with the respective checks on loads and stores. Link: https://linux-review.googlesource.com/id/Ic6d40803c57dcc6331bd97fbb9a60b0d38a65a36 Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Peter Collingbourne <[email protected]> Reviewed-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Peter Collingbourne <[email protected]> Cc: Evgenii Stepanov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/kasan: switch from strlcpy to strscpyZhiyuan Dai1-1/+1
strlcpy is marked as deprecated in Documentation/process/deprecated.rst, and there is no functional difference when the caller expects truncation (when not checking the return value). strscpy is relatively better as it also avoids scanning the whole source string. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Zhiyuan Dai <[email protected]> Acked-by: Alexander Potapenko <[email protected]> Reviewed-by: Andrey Konovalov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30pagewalk: prefix struct kernel-doc descriptionsLukas Bulwahn1-2/+2
The script './scripts/kernel-doc -none ./include/linux/pagewalk.h' reports: include/linux/pagewalk.h:37: warning: cannot understand function prototype: 'struct mm_walk_ops ' include/linux/pagewalk.h:85: warning: cannot understand function prototype: 'struct mm_walk ' A kernel-doc description for a structure requires to prefix the struct name with the keyword 'struct'. So, do that such that no further kernel-doc warnings are reported for this file. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Lukas Bulwahn <[email protected]> Cc: Joe Perches <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Ralf Ramsauer <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30MAINTAINERS: assign pagewalk.h to MEMORY MANAGEMENTLukas Bulwahn1-0/+1
Patch series "kernel-doc and MAINTAINERS clean-up". Roughly 900 warnings of about 21.000 kernel-doc warnings in the kernel tree warn with 'cannot understand function prototype:', i.e., the kernel-doc parser cannot parse the function's signature. The majority, about 600 cases of those, are just struct definitions following the kernel-doc description. Further, spot-check investigations suggest that the authors of the specific kernel-doc descriptions simply were not aware that the general format for a kernel-doc description for a structure requires to prefix the struct name with the keyword 'struct', as in 'struct struct_name - Brief description.'. Details on kernel-doc are at the Link below. Without the struct keyword, kernel-doc does not check if the kernel-doc description fits to the actual struct definition in the source code. Fortunately, in roughly a quarter of these cases, the kernel-doc description is actually complete wrt. its corresponding struct definition. So, the trivial change adding the struct keyword will allow us to keep the kernel-doc descriptions more consistent for future changes, by checking for new kernel-doc warnings. Also, some of the files in ./include/ are not assigned to a specific MAINTAINERS section and hence have no dedicated maintainer. So, if needed, the files in ./include/ are also assigned to the fitting MAINTAINERS section, as I need to identify whom to send the clean-up patch anyway. Here is the change from this kernel-doc janitorial work in the ./include/ directory for MEMORY MANAGEMENT. This patch (of 2): Commit a520110e4a15 ("mm: split out a new pagewalk.h header from mm.h") adds a new file in ./include/linux, but misses to update MAINTAINERS accordingly. Hence, ./scripts/get_maintainers.pl include/linux/pagewalk.h points only to lkml as general fallback for all files, whereas the original include/linux/mm.h clearly marks this file part of MEMORY MANAGEMENT. Assign include/linux/pagewalk.h to MEMORY MANAGEMENT. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Lukas Bulwahn <[email protected]> Cc: Joe Perches <[email protected]> Cc: Ralf Ramsauer <[email protected]> Cc: Jonathan Corbet <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/doc: add mm.h and mm_types.h to the mm-api documentMatthew Wilcox (Oracle)1-0/+4
kerneldoc in include/linux/mm.h and include/linux/mm_types.h wasn't being included in the html build. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Acked-by: Mike Rapoport <[email protected]> Cc: John Hubbard <[email protected]> Cc: Jonathan Corbet <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/doc: turn fault flags into an enumMatthew Wilcox (Oracle)1-14/+15
The kernel-doc script complains about include/linux/mm.h:425: warning: wrong kernel-doc identifier on line: * Fault flag definitions. I don't know how to document a series of #defines, so turn these definitions into an enum and document that instead. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Acked-by: Mike Rapoport <[email protected]> Cc: John Hubbard <[email protected]> Cc: Jonathan Corbet <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/doc: fix page_maybe_dma_pinned kerneldocMatthew Wilcox (Oracle)1-5/+5
make htmldocs reports: include/linux/mm.h:1341: warning: Excess function parameter 'Return' description in 'page_maybe_dma_pinned' Fix a few other formatting nits while I'm editing this description. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Acked-by: Mike Rapoport <[email protected]> Reviewed-by: John Hubbard <[email protected]> Cc: Jonathan Corbet <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/doc: fix fault_flag_allow_retry_first kerneldocMatthew Wilcox (Oracle)1-0/+1
make htmldocs reports: include/linux/mm.h:496: warning: Function parameter or member 'flags' not described in 'fault_flag_allow_retry_first' Add a description. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Cc: John Hubbard <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Jonathan Corbet <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/vmalloc: remove an empty lineUladzislau Rezki (Sony)1-1/+0
Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Uladzislau Rezki (Sony) <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Oleksiy Avramchenko <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Steven Rostedt <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm/vmalloc: refactor the preloading loagicUladzislau Rezki (Sony)1-33/+27
Instead of keeping open-coded style, move the code related to preloading into a separate function. Therefore introduce the preload_this_cpu_lock() routine that prelaods a current CPU with one extra vmap_area object. There is no functional change as a result of this patch. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Uladzislau Rezki (Sony) <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Oleksiy Avramchenko <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Steven Rostedt <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30vm/test_vmalloc.sh: adapt for updated driver interfaceUladzislau Rezki (Sony)1-10/+11
A 'single_cpu_test' parameter is odd and it does not exist anymore. Instead there was introduced a 'nr_threads' one. If it is not set it behaves as the former parameter. That is why update a "stress mode" according to this change specifying number of workers which are equal to number of CPUs. Also update an output of help message based on a new interface. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Uladzislau Rezki (Sony) <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Oleksiy Avramchenko <[email protected]> Cc: Steven Rostedt <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30lib/test_vmalloc.c: add a new 'nr_threads' parameterUladzislau Rezki (Sony)1-48/+40
By using this parameter we can specify how many workers are created to perform vmalloc tests. By default it is one CPU. The maximum value is set to 1024. As a result of this change a 'single_cpu_test' one becomes obsolete, therefore it is no longer needed. [[email protected]: extend max value of nr_threads parameter] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Uladzislau Rezki (Sony) <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Oleksiy Avramchenko <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Steven Rostedt <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30lib/test_vmalloc.c: remove two kvfree_rcu() testsUladzislau Rezki (Sony)1-40/+0
Remove two test cases related to kvfree_rcu() and SLAB. Those are considered as redundant now, because similar test functionality has recently been introduced in the "rcuscale" RCU test-suite. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Uladzislau Rezki (Sony) <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Oleksiy Avramchenko <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Shuah Khan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-04-30mm: vmalloc: prevent use after free in _vm_unmap_aliasesVijayanand Jitta1-1/+1
A potential use after free can occur in _vm_unmap_aliases where an already freed vmap_area could be accessed, Consider the following scenario: Process 1 Process 2 __vm_unmap_aliases __vm_unmap_aliases purge_fragmented_blocks_allcpus rcu_read_lock() rcu_read_lock() list_del_rcu(&vb->free_list) list_for_each_entry_rcu(vb .. ) __purge_vmap_area_lazy kmem_cache_free(va) va_start = vb->va->va_start Here Process 1 is in purge path and it does list_del_rcu on vmap_block and later frees the vmap_area, since Process 2 was holding the rcu lock at this time vmap_block will still be present in and Process 2 accesse it and thereby it tries to access vmap_area of that vmap_block which was already freed by Process 1 and this results in use after free. Fix this by adding a check for vb->dirty before accessing vmap_area structure since vb->dirty will be set to VMAP_BBMAP_BITS in purge path checking for this will prevent the use after free. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Vijayanand Jitta <[email protected]> Reviewed-by: Uladzislau Rezki (Sony) <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>