diff options
author | Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> | 2020-10-15 20:05:10 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-16 11:11:14 -0700 |
commit | f14312e1ed1e40dfed38bb70eb9a71d97a6b60f4 (patch) | |
tree | 82b6dde125994082d2aa9a4d8f04a3d3565c2079 /mm/debug_vm_pgtable.c | |
parent | 401035d5c456691f79fbcc08eb6ee5479c30b606 (diff) | |
download | lwn-f14312e1ed1e40dfed38bb70eb9a71d97a6b60f4.tar.gz lwn-f14312e1ed1e40dfed38bb70eb9a71d97a6b60f4.zip |
mm/debug_vm_pgtable: avoid doing memory allocation with pgtable_t mapped.
With highmem, pte_alloc_map() keep the level4 page table mapped using
kmap_atomic(). Avoid doing new memory allocation with page table mapped
like above.
[ 9.409233] BUG: sleeping function called from invalid context at mm/page_alloc.c:4822
[ 9.410557] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper
[ 9.411932] no locks held by swapper/1.
[ 9.412595] CPU: 0 PID: 1 Comm: swapper Not tainted 5.9.0-rc3-00323-gc50eb1ed654b5 #2
[ 9.413824] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
[ 9.415207] Call Trace:
[ 9.415651] ? ___might_sleep.cold+0xa7/0xcc
[ 9.416367] ? __alloc_pages_nodemask+0x14c/0x5b0
[ 9.417055] ? swap_migration_tests+0x50/0x293
[ 9.417704] ? debug_vm_pgtable+0x4bc/0x708
[ 9.418287] ? swap_migration_tests+0x293/0x293
[ 9.418911] ? do_one_initcall+0x82/0x3cb
[ 9.419465] ? parse_args+0x1bd/0x280
[ 9.419983] ? rcu_read_lock_sched_held+0x36/0x60
[ 9.420673] ? trace_initcall_level+0x1f/0xf3
[ 9.421279] ? trace_initcall_level+0xbd/0xf3
[ 9.421881] ? do_basic_setup+0x9d/0xdd
[ 9.422410] ? do_basic_setup+0xc3/0xdd
[ 9.422938] ? kernel_init_freeable+0x72/0xa3
[ 9.423539] ? rest_init+0x134/0x134
[ 9.424055] ? kernel_init+0x5/0x12c
[ 9.424574] ? ret_from_fork+0x19/0x30
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lkml.kernel.org/r/20200913110327.645310-1-aneesh.kumar@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/debug_vm_pgtable.c')
-rw-r--r-- | mm/debug_vm_pgtable.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index 9a0a42a4f08d..c05d9dcf7891 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -943,7 +943,13 @@ static int __init debug_vm_pgtable(void) p4dp = p4d_alloc(mm, pgdp, vaddr); pudp = pud_alloc(mm, p4dp, vaddr); pmdp = pmd_alloc(mm, pudp, vaddr); - ptep = pte_alloc_map(mm, pmdp, vaddr); + /* + * Allocate pgtable_t + */ + if (pte_alloc(mm, pmdp)) { + pr_err("pgtable allocation failed\n"); + return 1; + } /* * Save all the page table page addresses as the page table @@ -997,8 +1003,7 @@ static int __init debug_vm_pgtable(void) * proper page table lock. */ - ptl = pte_lockptr(mm, pmdp); - spin_lock(ptl); + ptep = pte_offset_map_lock(mm, pmdp, vaddr, &ptl); pte_clear_tests(mm, ptep, pte_aligned, vaddr, prot); pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot); pte_unmap_unlock(ptep, ptl); |