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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Queue-Id: 36AD040007 X-Rspamd-Server: rspam10 X-Stat-Signature: 9tzj9hdcwug6mx31p81m1x1xzyaieyz1 X-HE-Tag: 1767716533-104795 X-HE-Meta: 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 4GMIF7bB 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Now, as the page_ext holds count of IOMMU mappings, we can use it to assert that any page allocated/freed is indeed not in the IOMMU. The sanitizer doesn=E2=80=99t protect against mapping/unmapping during this period. However, that=E2=80=99s less harmful as the page is not used by the kernel. Reviewed-by: Lu Baolu Signed-off-by: Mostafa Saleh --- drivers/iommu/iommu-debug-pagealloc.c | 23 +++++++++++++++++++++++ include/linux/iommu-debug-pagealloc.h | 14 ++++++++++++++ include/linux/mm.h | 5 +++++ 3 files changed, 42 insertions(+) diff --git a/drivers/iommu/iommu-debug-pagealloc.c b/drivers/iommu/iommu-de= bug-pagealloc.c index 86ccb310a4a8..5353417e64f9 100644 --- a/drivers/iommu/iommu-debug-pagealloc.c +++ b/drivers/iommu/iommu-debug-pagealloc.c @@ -9,6 +9,7 @@ #include #include #include +#include =20 #include "iommu-priv.h" =20 @@ -73,6 +74,28 @@ static size_t iommu_debug_page_size(struct iommu_domain = *domain) return 1UL << __ffs(domain->pgsize_bitmap); } =20 +static bool iommu_debug_page_count(const struct page *page) +{ + unsigned int ref; + struct page_ext *page_ext =3D page_ext_get(page); + struct iommu_debug_metadata *d =3D get_iommu_data(page_ext); + + ref =3D atomic_read(&d->ref); + page_ext_put(page_ext); + return ref !=3D 0; +} + +void __iommu_debug_check_unmapped(const struct page *page, int numpages) +{ + while (numpages--) { + if (WARN_ON(iommu_debug_page_count(page))) { + pr_warn("iommu: Detected page leak!\n"); + dump_page_owner(page); + } + page++; + } +} + void __iommu_debug_map(struct iommu_domain *domain, phys_addr_t phys, size= _t size) { size_t off, end; diff --git a/include/linux/iommu-debug-pagealloc.h b/include/linux/iommu-de= bug-pagealloc.h index a439d6815ca1..46c3c1f70150 100644 --- a/include/linux/iommu-debug-pagealloc.h +++ b/include/linux/iommu-debug-pagealloc.h @@ -13,6 +13,20 @@ DECLARE_STATIC_KEY_FALSE(iommu_debug_initialized); =20 extern struct page_ext_operations page_iommu_debug_ops; =20 +void __iommu_debug_check_unmapped(const struct page *page, int numpages); + +static inline void iommu_debug_check_unmapped(const struct page *page, int= numpages) +{ + if (static_branch_unlikely(&iommu_debug_initialized)) + __iommu_debug_check_unmapped(page, numpages); +} + +#else +static inline void iommu_debug_check_unmapped(const struct page *page, + int numpages) +{ +} + #endif /* CONFIG_IOMMU_DEBUG_PAGEALLOC */ =20 #endif /* __LINUX_IOMMU_DEBUG_PAGEALLOC_H */ diff --git a/include/linux/mm.h b/include/linux/mm.h index 6f959d8ca4b4..32205d2a24b2 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -36,6 +36,7 @@ #include #include #include +#include =20 struct mempolicy; struct anon_vma; @@ -4133,12 +4134,16 @@ extern void __kernel_map_pages(struct page *page, i= nt numpages, int enable); #ifdef CONFIG_DEBUG_PAGEALLOC static inline void debug_pagealloc_map_pages(struct page *page, int numpag= es) { + iommu_debug_check_unmapped(page, numpages); + if (debug_pagealloc_enabled_static()) __kernel_map_pages(page, numpages, 1); } =20 static inline void debug_pagealloc_unmap_pages(struct page *page, int nump= ages) { + iommu_debug_check_unmapped(page, numpages); + if (debug_pagealloc_enabled_static()) __kernel_map_pages(page, numpages, 0); } --=20 2.52.0.351.gbe84eed79e-goog