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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: B84D8140018 X-Stat-Signature: jmuuqp7phjyqwk1kz9a7e9qtqpmt7d5b X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1767979568-18685 X-HE-Meta: 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 2PMEcmBH YgoBUNrHqL5RvAJKLcm4xZYvDbCDWTAsV0sKoXywEDHcbUUeD7O/CfXgFQ98j4PQUv8FVThfk1E4OFpo35Ar1q/icuCK4gX/WRc0yeK13FA0vAF0sTKEo4wxn3LbFjIQdy3YdMx2kwSffgpvCTPzmHWy8JwCGYFirBRYLthYdbGijziSWpZO+bKblbzWQZdOELwjiBIUcD9RCCsY5Mo1WCQbzi4t7Gd8hN8hFp7BT16HfGm/DmwyjdoIpAxR5iy8nJcIbCEmqSvTn8Ybj/Pk+8x4VlxDtmLUQWa4Z2Btmb2t5XF9W7dHXWKxUuZZaTnTe0YmW0bpXzaqUDtRRwnX7x8KKF0w/tbAg6HWVFhGa4nKc7N2BhwwDwfPCQVDcPFRw5AXsIqs5T5DE3rSWVIr1ORPzlwk3LGuMw2JzEQon4jR3678durlcrEe2eZdkV9cghSD6aR2ymaFNuGQIsOVhhsO7RvmA8elIJzQdzFgxkAwdK090ak1CZfFL9PBrc/Xlgeo04sPdR0MkEGnKYVWobG7ef12dHq2QjWsSgRH+wUSmlIuxNOrO2C8MUd1YUiyMMOa/oRiREIuh7l6NasRNsdmsgxUFuP3ojPTI0q6ySSCy16Y= 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 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 9eb49e1230ee..c080a38f45a4 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 2.52.0.457.g6b5491de43-goog