kernel/linux.git/mm/vmalloc.c, branch v5.10.257

mm/vmalloc: leave lazy MMU mode on PTE mapping error

2025-08-28T14:22:29+00:00

commit fea18c686320a53fce7ad62a87a3e1d10ad02f31 upstream. vmap_pages_pte_range() enters the lazy MMU mode, but fails to leave it in case an error is encountered. Link: https://lkml.kernel.org/r/20250623075721.2817094-1-agordeev@linux.ibm.com Fixes: 2ba3e6947aed ("mm/vmalloc: track which page-table levels were modified") Signed-off-by: Alexander Gordeev Reported-by: kernel test robot Reported-by: Dan Carpenter Closes: https://lore.kernel.org/r/202506132017.T1l1l6ME-lkp@intel.com/ Reviewed-by: Ryan Roberts Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

vmalloc: fix accounting with i915

2025-02-01T17:22:30+00:00

[ Upstream commit a2e740e216f5bf49ccb83b6d490c72a340558a43 ] If the caller of vmap() specifies VM_MAP_PUT_PAGES (currently only the i915 driver), we will decrement nr_vmalloc_pages and MEMCG_VMALLOC in vfree(). These counters are incremented by vmalloc() but not by vmap() so this will cause an underflow. Check the VM_MAP_PUT_PAGES flag before decrementing either counter. Link: https://lkml.kernel.org/r/20241211202538.168311-1-willy@infradead.org Fixes: b944afc9d64d ("mm: add a VM_MAP_PUT_PAGES flag for vmap") Signed-off-by: Matthew Wilcox (Oracle) Acked-by: Johannes Weiner Reviewed-by: Shakeel Butt Reviewed-by: Balbir Singh Acked-by: Michal Hocko Cc: Christoph Hellwig Cc: Muchun Song Cc: Roman Gushchin Cc: "Uladzislau Rezki (Sony)" Cc: Signed-off-by: Andrew Morton Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

mm: add a call to flush_cache_vmap() in vmap_pfn()

2023-08-30T14:23:14+00:00

commit a50420c79731fc5cf27ad43719c1091e842a2606 upstream. flush_cache_vmap() must be called after new vmalloc mappings are installed in the page table in order to allow architectures to make sure the new mapping is visible. It could lead to a panic since on some architectures (like powerpc), the page table walker could see the wrong pte value and trigger a spurious page fault that can not be resolved (see commit f1cb8f9beba8 ("powerpc/64s/radix: avoid ptesync after set_pte and ptep_set_access_flags")). But actually the patch is aiming at riscv: the riscv specification allows the caching of invalid entries in the TLB, and since we recently removed the vmalloc page fault handling, we now need to emit a tlb shootdown whenever a new vmalloc mapping is emitted (https://lore.kernel.org/linux-riscv/20230725132246.817726-1-alexghiti@rivosinc.com/). That's a temporary solution, there are ways to avoid that :) Link: https://lkml.kernel.org/r/20230809164633.1556126-1-alexghiti@rivosinc.com Fixes: 3e9a9e256b1e ("mm: add a vmap_pfn function") Reported-by: Dylan Jhong Closes: https://lore.kernel.org/linux-riscv/ZMytNY2J8iyjbPPy@atctrx.andestech.com/ Signed-off-by: Alexandre Ghiti Reviewed-by: Christoph Hellwig Reviewed-by: Palmer Dabbelt Acked-by: Palmer Dabbelt Reviewed-by: Dylan Jhong Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

mm/vmalloc.c: fix potential memory leak

2021-01-19T17:27:21+00:00

commit c22ee5284cf58017fa8c6d21d8f8c68159b6faab upstream. In VM_MAP_PUT_PAGES case, we should put pages and free array in vfree. But we missed to set area->nr_pages in vmap(). So we would fail to put pages in __vunmap() because area->nr_pages = 0. Link: https://lkml.kernel.org/r/20210107123541.39206-1-linmiaohe@huawei.com Fixes: b944afc9d64d ("mm: add a VM_MAP_PUT_PAGES flag for vmap") Signed-off-by: Shijie Luo Signed-off-by: Miaohe Lin Reviewed-by: Uladzislau Rezki (Sony) Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

mm/vmalloc.c: fix kasan shadow poisoning size

2020-12-30T10:53:55+00:00

[ Upstream commit c041098c690fe53cea5d20c62f128a4f7a5c19fe ] The size of vm area can be affected by the presence or not of the guard page. In particular when VM_NO_GUARD is present, the actual accessible size has to be considered like the real size minus the guard page. Currently kasan does not keep into account this information during the poison operation and in particular tries to poison the guard page as well. This approach, even if incorrect, does not cause an issue because the tags for the guard page are written in the shadow memory. With the future introduction of the Tag-Based KASAN, being the guard page inaccessible by nature, the write tag operation on this page triggers a fault. Fix kasan shadow poisoning size invoking get_vm_area_size() instead of accessing directly the field in the data structure to detect the correct value. Link: https://lkml.kernel.org/r/20201027160213.32904-1-vincenzo.frascino@arm.com Fixes: d98c9e83b5e7c ("kasan: fix crashes on access to memory mapped by vm_map_ram()") Signed-off-by: Vincenzo Frascino Cc: Andrey Konovalov Cc: Dmitry Vyukov Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Marco Elver Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

mm/vmalloc: Fix unlock order in s_stop()

2020-12-30T10:53:55+00:00

[ Upstream commit 0a7dd4e901b8a4ee040ba953900d1d7120b34ee5 ] When multiple locks are acquired, they should be released in reverse order. For s_start() and s_stop() in mm/vmalloc.c, that is not the case. s_start: mutex_lock(&vmap_purge_lock); spin_lock(&vmap_area_lock); s_stop : mutex_unlock(&vmap_purge_lock); spin_unlock(&vmap_area_lock); This unlock sequence, though allowed, is not optimal. If a waiter is present, mutex_unlock() will need to go through the slowpath of waking up the waiter with preemption disabled. Fix that by releasing the spinlock first before the mutex. Link: https://lkml.kernel.org/r/20201213180843.16938-1-longman@redhat.com Fixes: e36176be1c39 ("mm/vmalloc: rework vmap_area_lock") Signed-off-by: Waiman Long Reviewed-by: Uladzislau Rezki (Sony) Reviewed-by: David Hildenbrand Cc: Matthew Wilcox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

mm: remove the filename in the top of file comment in vmalloc.c

2020-10-18T16:27:10+00:00

No point in having the filename inside the file. Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Cc: Uladzislau Rezki (Sony) Link: https://lkml.kernel.org/r/20201002124035.1539300-3-hch@lst.de Signed-off-by: Linus Torvalds

mm: cleanup the gfp_mask handling in __vmalloc_area_node

2020-10-18T16:27:10+00:00

Patch series "two small vmalloc cleanups". This patch (of 2): __vmalloc_area_node currently has four different gfp_t variables to just express this simple logic: - use the passed in mask, plus __GFP_NOWARN and __GFP_HIGHMEM (if suitable) for the underlying page allocation - use just the reclaim flags from the passed in mask plus __GFP_ZERO for allocating the page array Simplify this down to just use the pre-existing nested_gfp as-is for the page array allocation, and just the passed in gfp_mask for the page allocation, after conditionally ORing __GFP_HIGHMEM into it. This also makes the allocation warning a little more correct. Also initialize two variables at the time of declaration while touching this area. Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Cc: Uladzislau Rezki (Sony) Link: https://lkml.kernel.org/r/20201002124035.1539300-1-hch@lst.de Link: https://lkml.kernel.org/r/20201002124035.1539300-2-hch@lst.de Signed-off-by: Linus Torvalds

mm: remove alloc_vm_area

2020-10-18T16:27:10+00:00

All users are gone now. Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Cc: Boris Ostrovsky Cc: Chris Wilson Cc: Jani Nikula Cc: Joonas Lahtinen Cc: Juergen Gross Cc: Matthew Auld Cc: "Matthew Wilcox (Oracle)" Cc: Minchan Kim Cc: Nitin Gupta Cc: Peter Zijlstra Cc: Rodrigo Vivi Cc: Stefano Stabellini Cc: Tvrtko Ursulin Cc: Uladzislau Rezki (Sony) Link: https://lkml.kernel.org/r/20201002122204.1534411-12-hch@lst.de Signed-off-by: Linus Torvalds

mm: add a vmap_pfn function

2020-10-18T16:27:10+00:00

Add a proper helper to remap PFNs into kernel virtual space so that drivers don't have to abuse alloc_vm_area and open coded PTE manipulation for it. Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Cc: Boris Ostrovsky Cc: Chris Wilson Cc: Jani Nikula Cc: Joonas Lahtinen Cc: Juergen Gross Cc: Matthew Auld Cc: "Matthew Wilcox (Oracle)" Cc: Minchan Kim Cc: Nitin Gupta Cc: Peter Zijlstra Cc: Rodrigo Vivi Cc: Stefano Stabellini Cc: Tvrtko Ursulin Cc: Uladzislau Rezki (Sony) Link: https://lkml.kernel.org/r/20201002122204.1534411-4-hch@lst.de Signed-off-by: Linus Torvalds