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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: 66s384dtq3w55h5jgx8fi9y8ikr6nyc9 X-Rspam-User: X-Rspamd-Queue-Id: CD34BA0005 X-Rspamd-Server: rspam10 X-HE-Tag: 1759512771-342446 X-HE-Meta: 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 BH/3Z7Us 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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. Signed-off-by: Mostafa Saleh --- drivers/iommu/iommu-debug.c | 22 ++++++++++++++++++++++ include/linux/iommu-debug.h | 1 + include/linux/mm.h | 7 +++++++ 3 files changed, 30 insertions(+) diff --git a/drivers/iommu/iommu-debug.c b/drivers/iommu/iommu-debug.c index cec8f594c7fa..09157fef697e 100644 --- a/drivers/iommu/iommu-debug.c +++ b/drivers/iommu/iommu-debug.c @@ -71,6 +71,28 @@ static size_t iommu_debug_page_size(struct iommu_domain = *domain) return 1UL << __ffs(domain->pgsize_bitmap); } =20 +static unsigned int iommu_debug_page_count(unsigned long phys) +{ + unsigned int ref; + struct page_ext *page_ext =3D get_iommu_page_ext(phys); + struct iommu_debug_metadate *d =3D get_iommu_data(page_ext); + + ref =3D atomic_read(&d->ref); + page_ext_put(page_ext); + return ref; +} + +void iommu_debug_check_unmapped(const struct page *page, int numpages) +{ + if (!static_branch_likely(&iommu_debug_initialized)) + return; + + while (numpages--) { + WARN_ON(iommu_debug_page_count(page_to_phys(page))); + page++; + } +} + void iommu_debug_map(struct iommu_domain *domain, phys_addr_t phys, size_t= size) { size_t off; diff --git a/include/linux/iommu-debug.h b/include/linux/iommu-debug.h index 8d3ea661660f..aaf893cfafd0 100644 --- a/include/linux/iommu-debug.h +++ b/include/linux/iommu-debug.h @@ -17,6 +17,7 @@ void iommu_debug_map(struct iommu_domain *domain, phys_ad= dr_t phys, size_t size) void iommu_debug_unmap(struct iommu_domain *domain, unsigned long iova, si= ze_t size); void iommu_debug_remap(struct iommu_domain *domain, unsigned long iova, si= ze_t size); void iommu_debug_init(void); +void iommu_debug_check_unmapped(const struct page *page, int numpages); =20 #endif /* CONFIG_IOMMU_DEBUG_PAGEALLOC */ =20 diff --git a/include/linux/mm.h b/include/linux/mm.h index 06978b4dbeb8..00f5de44faa0 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; @@ -3806,12 +3807,18 @@ 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) { +#ifdef CONFIG_IOMMU_DEBUG_PAGEALLOC + iommu_debug_check_unmapped(page, numpages); +#endif 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) { +#ifdef CONFIG_IOMMU_DEBUG_PAGEALLOC + iommu_debug_check_unmapped(page, numpages); +#endif if (debug_pagealloc_enabled_static()) __kernel_map_pages(page, numpages, 0); } --=20 2.51.0.618.g983fd99d29-goog