linux/mm
Christoph Hellwig 37dcc673d0 frontswap: don't call ->init if no ops are registered
If no frontswap module (i.e.  zswap) was registered, frontswap_ops will be
NULL.  In such situation, swapon crashes with the following stack trace:

  Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000000000000000
  Mem abort info:
    ESR = 0x0000000096000004
    EC = 0x25: DABT (current EL), IL = 32 bits
    SET = 0, FnV = 0
    EA = 0, S1PTW = 0
    FSC = 0x04: level 0 translation fault
  Data abort info:
    ISV = 0, ISS = 0x00000004
    CM = 0, WnR = 0
  user pgtable: 4k pages, 48-bit VAs, pgdp=00000020a4fab000
  [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
  Internal error: Oops: 96000004 [#1] SMP
  Modules linked in: zram fsl_dpaa2_eth pcs_lynx phylink ahci_qoriq crct10dif_ce ghash_ce sbsa_gwdt fsl_mc_dpio nvme lm90 nvme_core at803x xhci_plat_hcd rtc_fsl_ftm_alarm xgmac_mdio ahci_platform i2c_imx ip6_tables ip_tables fuse
  Unloaded tainted modules: cppc_cpufreq():1
  CPU: 10 PID: 761 Comm: swapon Not tainted 6.0.0-rc2-00454-g22100432cf14 #1
  Hardware name: SolidRun Ltd. SolidRun CEX7 Platform, BIOS EDK II Jun 21 2022
  pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
  pc : frontswap_init+0x38/0x60
  lr : __do_sys_swapon+0x8a8/0x9f4
  sp : ffff80000969bcf0
  x29: ffff80000969bcf0 x28: ffff37bee0d8fc00 x27: ffff80000a7f5000
  x26: fffffcdefb971e80 x25: ffffaba797453b90 x24: 0000000000000064
  x23: ffff37c1f209d1a8 x22: ffff37bee880e000 x21: ffffaba797748560
  x20: ffff37bee0d8fce4 x19: ffffaba797748488 x18: 0000000000000014
  x17: 0000000030ec029a x16: ffffaba795a479b0 x15: 0000000000000000
  x14: 0000000000000000 x13: 0000000000000030 x12: 0000000000000001
  x11: ffff37c63c0aba18 x10: 0000000000000000 x9 : ffffaba7956b8c88
  x8 : ffff80000969bcd0 x7 : 0000000000000000 x6 : 0000000000000000
  x5 : 0000000000000001 x4 : 0000000000000000 x3 : ffffaba79730f000
  x2 : ffff37bee0d8fc00 x1 : 0000000000000000 x0 : 0000000000000000
  Call trace:
  frontswap_init+0x38/0x60
  __do_sys_swapon+0x8a8/0x9f4
  __arm64_sys_swapon+0x28/0x3c
  invoke_syscall+0x78/0x100
  el0_svc_common.constprop.0+0xd4/0xf4
  do_el0_svc+0x38/0x4c
  el0_svc+0x34/0x10c
  el0t_64_sync_handler+0x11c/0x150
  el0t_64_sync+0x190/0x194
  Code: d000e283 910003fd f9006c41 f946d461 (f9400021)
  ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20220909130829.3262926-1-hch@lst.de
Fixes: 1da0d94a3e ("frontswap: remove support for multiple ops")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-26 12:14:34 -07:00
..
damon mm/damon/dbgfs: fix memory leak when using debugfs_lookup() 2022-09-11 16:22:31 -07:00
kasan - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
kfence - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
backing-dev.c writeback: avoid use-after-free after removing device 2022-08-28 14:02:43 -07:00
balloon_compaction.c mm: Convert all PageMovable users to movable_operations 2022-08-02 12:34:03 -04:00
bootmem_info.c bootmem: remove the vmemmap pages from kmemleak in put_page_bootmem 2022-08-28 14:02:45 -07:00
cma_debug.c mm/cma_debug.c: align the name buffer length as struct cma 2022-07-29 18:07:16 -07:00
cma_sysfs.c
cma.c Revert "mm/cma.c: remove redundant cma_mutex lock" 2022-05-13 15:11:26 -07:00
cma.h mm/cma: provide option to opt out from exposing pages on activation failure 2022-03-22 15:57:09 -07:00
compaction.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
debug_page_ref.c
debug_vm_pgtable.c docs: rename Documentation/vm to Documentation/mm 2022-06-27 12:52:53 -07:00
debug.c mm: unexport page_init_poison 2022-03-24 19:06:45 -07:00
dmapool.c mm/dmapool.c: revert "make dma pool to use kmalloc_node" 2022-01-15 16:30:28 +02:00
early_ioremap.c mm/early_ioremap: declare early_memremap_pgprot_adjust() 2022-03-22 15:57:11 -07:00
fadvise.c riscv: compat: syscall: Add compat_sys_call_table implementation 2022-04-26 13:36:25 -07:00
failslab.c mm: fix missing handler for __GFP_NOWARN 2022-05-19 14:08:55 -07:00
filemap.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
folio-compat.c mm/folio-compat: Remove migration compatibility functions 2022-08-02 12:34:04 -04:00
frontswap.c frontswap: don't call ->init if no ops are registered 2022-09-26 12:14:34 -07:00
gup_test.c mm: rename is_pinnable_page() to is_longterm_pinnable_page() 2022-07-17 17:14:27 -07:00
gup_test.h
gup.c mm: gup: fix the fast GUP race against THP collapse 2022-09-26 12:14:33 -07:00
highmem.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
hmm.c mm/hmm: fault non-owner device private entries 2022-07-29 11:33:37 -07:00
huge_memory.c mm/huge_memory: use pfn_to_online_page() in split_huge_pages_all() 2022-09-26 12:14:33 -07:00
hugetlb_cgroup.c hugetlb_cgroup: fix wrong hugetlb cgroup numa stat 2022-07-29 18:07:17 -07:00
hugetlb_vmemmap.c mm: hugetlb_vmemmap: use PTRS_PER_PTE instead of PMD_SIZE / PAGE_SIZE 2022-08-08 18:06:43 -07:00
hugetlb_vmemmap.h mm: hugetlb_vmemmap: improve hugetlb_vmemmap code readability 2022-08-08 18:06:43 -07:00
hugetlb.c mm/hugetlb: avoid corrupting page->mapping in hugetlb_mcopy_atomic_pte 2022-08-28 14:02:43 -07:00
hwpoison-inject.c mm/memory-failure: disable unpoison once hw error happens 2022-06-16 19:11:32 -07:00
init-mm.c kernel/fork: Initialize mm's PASID 2022-02-14 19:51:47 +01:00
internal.h - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
interval_tree.c
io-mapping.c
ioremap.c mm: ioremap: Add ioremap/iounmap_allowed() 2022-06-27 12:22:31 +01:00
Kconfig cxl for 6.0 2022-08-10 11:07:26 -07:00
Kconfig.debug Two followon fixes for the post-5.19 series "Use pageblock_order for cma 2022-05-27 11:40:49 -07:00
khugepaged.c mm: gup: fix the fast GUP race against THP collapse 2022-09-26 12:14:33 -07:00
kmemleak.c mm/kmemleak: prevent soft lockup in first object iteration loop of kmemleak_scan() 2022-06-16 19:48:32 -07:00
ksm.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
list_lru.c mm: kmem: make mem_cgroup_from_obj() vmalloc()-safe 2022-06-16 19:48:31 -07:00
maccess.c asm-generic updates for 5.18 2022-03-23 18:03:08 -07:00
madvise.c mm: fix madivse_pageout mishandling on non-LRU page 2022-09-26 12:14:33 -07:00
Makefile mm: shrinkers: introduce debugfs interface for memory shrinkers 2022-07-03 18:08:40 -07:00
mapping_dirty_helpers.c mm: move tlb_flush_pending inline helpers to mm_inline.h 2022-01-15 16:30:27 +02:00
memblock.c memblock updates for v5.20 2022-08-09 09:48:30 -07:00
memcontrol.c mm: memcontrol: fix potential oom_lock recursion deadlock 2022-07-29 18:07:18 -07:00
memfd.c memfd: fix F_SEAL_WRITE after shmem huge page allocated 2022-03-05 11:08:32 -08:00
memory_hotplug.c mm: use is_zone_movable_page() helper 2022-07-29 18:07:20 -07:00
memory-failure.c mm/memory-failure: fall back to vma_address() when ->notify_failure() fails 2022-09-11 16:22:30 -07:00
memory.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
mempolicy.c mm/mempolicy: remove unneeded out label 2022-07-29 18:07:16 -07:00
mempool.c mm/mempool: use might_alloc() 2022-06-16 19:48:30 -07:00
memremap.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
memtest.c
migrate_device.c mm/migrate_device.c: copy pte dirty bit to page 2022-09-11 16:22:30 -07:00
migrate.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
mincore.c mm: teach core mm about pte markers 2022-05-13 07:20:09 -07:00
mlock.c mm: handling Non-LRU pages returned by vm_normal_pages 2022-07-17 17:14:28 -07:00
mm_init.c
mmap_lock.c
mmap.c mm/hugetlb: fix hugetlb not supporting softdirty tracking 2022-08-20 15:17:45 -07:00
mmu_gather.c mm/mmu_gather: limit free batch count and add schedule point in tlb_batch_pages_flush 2022-04-28 23:16:12 -07:00
mmu_notifier.c mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove() 2022-04-21 20:01:10 -07:00
mmzone.c Folio changes for 5.18 2022-03-22 17:03:12 -07:00
mprotect.c mm/mprotect: only reference swap pfn page if type match 2022-08-28 14:02:46 -07:00
mremap.c Yang Shi has improved the behaviour of khugepaged collapsing of readonly 2022-05-26 12:32:41 -07:00
msync.c
nommu.c mm: nommu: pass a pointer to virt_to_page() 2022-07-17 17:14:37 -07:00
oom_kill.c mm/oom_kill.c: fix vm_oom_kill_table[] ifdeffery 2022-06-01 15:57:16 -07:00
page_alloc.c mm/page_alloc: fix race condition between build_all_zonelists and page allocation 2022-09-11 16:22:29 -07:00
page_counter.c mm/page_counter: remove an incorrect call to propagate_protected_usage() 2022-01-15 16:30:27 +02:00
page_ext.c mm: use for_each_online_node and node_online instead of open coding 2022-04-29 14:36:58 -07:00
page_idle.c mm: don't be stuck to rmap lock on reclaim path 2022-05-19 14:08:54 -07:00
page_io.c Yang Shi has improved the behaviour of khugepaged collapsing of readonly 2022-05-26 12:32:41 -07:00
page_isolation.c mm/page_isolation.c: fix one kernel-doc comment 2022-06-16 19:11:30 -07:00
page_owner.c Yang Shi has improved the behaviour of khugepaged collapsing of readonly 2022-05-26 12:32:41 -07:00
page_poison.c
page_reporting.c
page_reporting.h
page_table_check.c Six hotfixes. One from Miaohe Lin is considered a minor thing so it isn't 2022-05-27 11:29:35 -07:00
page_vma_mapped.c mm/page_vma_mapped.c: use helper function huge_pte_lock 2022-07-17 17:14:47 -07:00
page-writeback.c writeback: avoid use-after-free after removing device 2022-08-28 14:02:43 -07:00
pagewalk.c
percpu-internal.h percpu: improve percpu_alloc_percpu event trace 2022-05-13 07:20:18 -07:00
percpu-km.c
percpu-stats.c mm: use vmalloc_array and vcalloc for array allocations 2022-03-08 09:30:46 -05:00
percpu-vm.c
percpu.c mm: percpu: use kmemleak_ignore_phys() instead of kmemleak_free() 2022-07-17 17:14:47 -07:00
pgalloc-track.h
pgtable-generic.c mm: avoid unnecessary flush on change_huge_pmd() 2022-05-13 07:20:05 -07:00
process_vm_access.c
ptdump.c mm: sparsemem: use page table lock to protect kernel pmd operations 2022-03-22 15:57:08 -07:00
readahead.c filemap: Fix serialization adding transparent huge pages to page cache 2022-06-23 12:22:00 -04:00
rmap.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
rodata_test.c
secretmem.c mm: fix dereferencing possible ERR_PTR 2022-09-11 16:22:31 -07:00
shmem.c shmem: update folio if shmem_replace_page() updates the page 2022-08-28 14:02:43 -07:00
shrinker_debug.c mm: shrinkers: fix double kfree on shrinker name 2022-07-29 18:07:13 -07:00
shuffle.c
shuffle.h
slab_common.c mm/slab_common: move generic bulk alloc/free functions to SLOB 2022-07-20 13:30:12 +02:00
slab.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
slab.h mm/slab_common: move generic bulk alloc/free functions to SLOB 2022-07-20 13:30:12 +02:00
slob.c mm/slab_common: move generic bulk alloc/free functions to SLOB 2022-07-20 13:30:12 +02:00
slub.c mm/sl[au]b: use own bulk free function when bulk alloc failed 2022-07-20 13:30:11 +02:00
sparse-vmemmap.c mm: hugetlb_vmemmap: move vmemmap code related to HugeTLB to hugetlb_vmemmap.c 2022-08-08 18:06:42 -07:00
sparse.c mm: memory_hotplug: enumerate all supported section flags 2022-07-03 18:08:49 -07:00
swap_cgroup.c mm: use vmalloc_array and vcalloc for array allocations 2022-03-08 09:30:46 -05:00
swap_slots.c arm64: enable THP_SWAP for arm64 2022-07-20 10:52:40 +01:00
swap_state.c mm: fix VM_BUG_ON in __delete_from_swap_cache() 2022-09-11 16:22:31 -07:00
swap.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
swap.h mm/khugepaged: try to free transhuge swapcache when possible 2022-07-03 18:08:52 -07:00
swapfile.c mm/swap: convert delete_from_swap_cache() to take a folio 2022-07-03 18:08:48 -07:00
truncate.c mm: Remove __delete_from_page_cache() 2022-06-29 08:51:05 -04:00
usercopy.c usercopy: use unsigned long instead of uintptr_t 2022-07-01 17:03:38 -07:00
userfaultfd.c mm/uffd: reset write protection when unregister with wp-mode 2022-08-20 15:17:45 -07:00
util.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
vmacache.c
vmalloc.c mm/vmalloc: extend __find_vmap_area() with one more argument 2022-07-03 18:08:41 -07:00
vmpressure.c mm/vmpressure: fix data-race with memcg->socket_pressure 2021-11-06 13:30:40 -07:00
vmscan.c vmscan: check folio_test_private(), not folio_get_private() 2022-09-11 16:22:31 -07:00
vmstat.c mm: add DEVICE_ZONE to FOR_ALL_ZONES 2022-08-20 15:17:45 -07:00
workingset.c mm: shrinkers: provide shrinkers with names 2022-07-03 18:08:40 -07:00
z3fold.c mm: Convert all PageMovable users to movable_operations 2022-08-02 12:34:03 -04:00
zbud.c
zpool.c zpool: remove the list of pools_head 2022-01-15 16:30:31 +02:00
zsmalloc.c mm/zsmalloc: do not attempt to free IS_ERR handle 2022-08-28 14:02:44 -07:00
zswap.c zswap: memcg accounting 2022-05-19 14:08:53 -07:00