diff options
| author | Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> | 2017-03-21 22:59:56 +0530 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-03-22 09:17:45 +0100 |
| commit | 66db324639335681f510ee8720d22ac237412564 (patch) | |
| tree | 76b284e09e19d9665e383fbebb089350519d7a07 /arch | |
| parent | aad6ccac0e4fddcfd1b04a2cbd95b550c59da23e (diff) | |
powerpc/mm/hugetlb: Filter out hugepage size not supported by page table layout
[ Upstream commit a525108cf1cc14651602d678da38fa627a76a724 ]
Without this if firmware reports 1MB page size support we will crash
trying to use 1MB as hugetlb page size.
echo 300 > /sys/kernel/mm/hugepages/hugepages-1024kB/nr_hugepages
kernel BUG at ./arch/powerpc/include/asm/hugetlb.h:19!
.....
....
[c0000000e2c27b30] c00000000029dae8 .hugetlb_fault+0x638/0xda0
[c0000000e2c27c30] c00000000026fb64 .handle_mm_fault+0x844/0x1d70
[c0000000e2c27d70] c00000000004805c .do_page_fault+0x3dc/0x7c0
[c0000000e2c27e30] c00000000000ac98 handle_page_fault+0x10/0x30
With fix, we don't enable 1MB as hugepage size.
bash-4.2# cd /sys/kernel/mm/hugepages/
bash-4.2# ls
hugepages-16384kB hugepages-16777216kB
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/mm/hugetlbpage.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index a5d3ecdabc44..035dfb65df4b 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -765,6 +765,24 @@ static int __init add_huge_page_size(unsigned long long size) if ((mmu_psize = shift_to_mmu_psize(shift)) < 0) return -EINVAL; +#ifdef CONFIG_PPC_BOOK3S_64 + /* + * We need to make sure that for different page sizes reported by + * firmware we only add hugetlb support for page sizes that can be + * supported by linux page table layout. + * For now we have + * Radix: 2M + * Hash: 16M and 16G + */ + if (radix_enabled()) { + if (mmu_psize != MMU_PAGE_2M) + return -EINVAL; + } else { + if (mmu_psize != MMU_PAGE_16M && mmu_psize != MMU_PAGE_16G) + return -EINVAL; + } +#endif + BUG_ON(mmu_psize_defs[mmu_psize].shift != shift); /* Return if huge page size has already been setup */ |