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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: jroth1hm5roscpmhwrn8dbnmx4qxmp43 X-Rspamd-Queue-Id: 7977840005 X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1768409016-749292 X-HE-Meta: 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 33mFw4GR 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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: Samiullah Khawaja Reviewed-by: Lu Baolu Reviewed-by: Pranjal Shrivastava 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 3ce3385588b2..a283b5dbe26f 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 @@ -75,6 +76,28 @@ 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 2.52.0.457.g6b5491de43-goog