diff options
| author | Christophe Leroy | 2018-11-29 14:07:07 +0000 |
|---|---|---|
| committer | Michael Ellerman | 2018-12-04 19:45:01 +1100 |
| commit | 1e03c7e2ea83b0acac7934e55943d1d4354baa43 (patch) | |
| tree | 7ac2eaf0eb7853578c9efe0a6dde7d708a0c5b3f /arch/powerpc/mm/hugetlbpage.c | |
| parent | 0356656284ca750f882b7eb81b9612bdbc90b2c4 (diff) | |
powerpc/mm: fix a warning when a cache is common to PGD and hugepages
While implementing TLB miss HW assistance on the 8xx, the following
warning was encountered:
[ 423.732965] WARNING: CPU: 0 PID: 345 at mm/slub.c:2412 ___slab_alloc.constprop.30+0x26c/0x46c
[ 423.733033] CPU: 0 PID: 345 Comm: mmap Not tainted 4.18.0-rc8-00664-g2dfff9121c55 #671
[ 423.733075] NIP: c0108f90 LR: c0109ad0 CTR: 00000004
[ 423.733121] REGS: c455bba0 TRAP: 0700 Not tainted (4.18.0-rc8-00664-g2dfff9121c55)
[ 423.733147] MSR: 00021032 <ME,IR,DR,RI> CR: 24224848 XER: 20000000
[ 423.733319]
[ 423.733319] GPR00: c0109ad0 c455bc50 c4521910 c60053c0 007080c0 c0011b34 c7fa41e0 c455be30
[ 423.733319] GPR08: 00000001 c00103a0 c7fa41e0 c49afcc4 24282842 10018840 c079b37c 00000040
[ 423.733319] GPR16: 73f00000 00210d00 00000000 00000001 c455a000 00000100 00000200 c455a000
[ 423.733319] GPR24: c60053c0 c0011b34 007080c0 c455a000 c455a000 c7fa41e0 00000000 00009032
[ 423.734190] NIP [c0108f90] ___slab_alloc.constprop.30+0x26c/0x46c
[ 423.734257] LR [c0109ad0] kmem_cache_alloc+0x210/0x23c
[ 423.734283] Call Trace:
[ 423.734326] [c455bc50] [00000100] 0x100 (unreliable)
[ 423.734430] [c455bcc0] [c0109ad0] kmem_cache_alloc+0x210/0x23c
[ 423.734543] [c455bcf0] [c0011b34] huge_pte_alloc+0xc0/0x1dc
[ 423.734633] [c455bd20] [c01044dc] hugetlb_fault+0x408/0x48c
[ 423.734720] [c455bdb0] [c0104b20] follow_hugetlb_page+0x14c/0x44c
[ 423.734826] [c455be10] [c00e8e54] __get_user_pages+0x1c4/0x3dc
[ 423.734919] [c455be80] [c00e9924] __mm_populate+0xac/0x140
[ 423.735020] [c455bec0] [c00db14c] vm_mmap_pgoff+0xb4/0xb8
[ 423.735127] [c455bf00] [c00f27c0] ksys_mmap_pgoff+0xcc/0x1fc
[ 423.735222] [c455bf40] [c000e0f8] ret_from_syscall+0x0/0x38
[ 423.735271] Instruction dump:
[ 423.735321] 7cbf482e 38fd0008 7fa6eb78 7fc4f378 4bfff5dd 7fe3fb78 4bfffe24 81370010
[ 423.735536] 71280004 41a2ff88 4840c571 4bffff80 <0fe00000> 4bfffeb8 81340010 712a0004
[ 423.735757] ---[ end trace e9b222919a470790 ]---
This warning occurs when calling kmem_cache_zalloc() on a
cache having a constructor.
In this case it happens because PGD cache and 512k hugepte cache are
the same size (4k). While a cache with constructor is created for
the PGD, hugepages create cache without constructor and uses
kmem_cache_zalloc(). As both expect a cache with the same size,
the hugepages reuse the cache created for PGD, hence the conflict.
In order to avoid this conflict, this patch:
- modifies pgtable_cache_add() so that a zeroising constructor is
added for any cache size.
- replaces calls to kmem_cache_zalloc() by kmem_cache_alloc()
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm/hugetlbpage.c')
| -rw-r--r-- | arch/powerpc/mm/hugetlbpage.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index c4f1263228b8..bc97874d7c74 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -70,7 +70,7 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp, num_hugepd = 1; } - new = kmem_cache_zalloc(cachep, pgtable_gfp_flags(mm, GFP_KERNEL)); + new = kmem_cache_alloc(cachep, pgtable_gfp_flags(mm, GFP_KERNEL)); BUG_ON(pshift > HUGEPD_SHIFT_MASK); BUG_ON((unsigned long)new & HUGEPD_SHIFT_MASK); @@ -701,10 +701,10 @@ static int __init hugetlbpage_init(void) * use pgt cache for hugepd. */ if (pdshift > shift) - pgtable_cache_add(pdshift - shift, NULL); + pgtable_cache_add(pdshift - shift); #if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx) else - pgtable_cache_add(PTE_T_ORDER, NULL); + pgtable_cache_add(PTE_T_ORDER); #endif } |