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| author | Anshuman Khandual <anshuman.khandual@arm.com> | 2024-12-02 12:14:07 +0530 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-02-17 11:35:53 +0100 |
| commit | 625da897cf17ceb7eb89b68d971df3a7052e4cf6 (patch) | |
| tree | 30ae671ab2453bb4749ddedd98b300d9ae89ed9e /arch | |
| parent | ce628048390dad80320d5a1f74de6ca1e1be91e7 (diff) | |
| download | linux-625da897cf17ceb7eb89b68d971df3a7052e4cf6.tar.gz linux-625da897cf17ceb7eb89b68d971df3a7052e4cf6.tar.bz2 linux-625da897cf17ceb7eb89b68d971df3a7052e4cf6.zip | |
arm64/mm: Ensure adequate HUGE_MAX_HSTATE
[ Upstream commit 1e5823c8e86de83a43d59a522b4de29066d3b306 ]
This asserts that HUGE_MAX_HSTATE is sufficient enough preventing potential
hugetlb_max_hstate runtime overflow in hugetlb_add_hstate() thus triggering
a BUG_ON() there after.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Link: https://lore.kernel.org/r/20241202064407.53807-1-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/mm/hugetlbpage.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 3215adf48a1b..98a2a0e64e25 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -519,6 +519,18 @@ pte_t huge_ptep_clear_flush(struct vm_area_struct *vma, static int __init hugetlbpage_init(void) { + /* + * HugeTLB pages are supported on maximum four page table + * levels (PUD, CONT PMD, PMD, CONT PTE) for a given base + * page size, corresponding to hugetlb_add_hstate() calls + * here. + * + * HUGE_MAX_HSTATE should at least match maximum supported + * HugeTLB page sizes on the platform. Any new addition to + * supported HugeTLB page sizes will also require changing + * HUGE_MAX_HSTATE as well. + */ + BUILD_BUG_ON(HUGE_MAX_HSTATE < 4); if (pud_sect_supported()) hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT); |