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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
| commit | f4cdf7ca9a1fdcca413157df19753f388a5a224e (patch) | |
| tree | 60a31895b2446cd7fa27514e8c2843534a0de0da /drivers/iommu/iommu-debug-pagealloc.c | |
| download | linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip | |
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab:
- v4l2-core: added ISP statistics support and per-block validation
- v4l2-core: Allow unknown HDR10 white point and luminance
- New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor
- New codec: Milos: VPU v2.0 codec support
- isp driver: gained support for Dreamchip RPPX1 ISP framework
- vsp1 driver: gained support for RZ/T2H and RZ/N2H
- Novalake driver: gained CVS support for new NVL hardware
- dvb-core: fix feed leak on failed DMX_ADD_PID
- several driver fixes, cleanups and minor improvements
* tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits)
media: ipu-bridge: check all DMI entries when overriding sensor rotation
media: v4l2-async: avoid deleting unlinked ASC entry on link error
media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement
media: intel/ipu6: fix async notifier cleanup leak on parse error
media: staging/ipu7: fix async notifier UAF on probe error path
media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path
media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem()
media: rcar-isp: Fix VSPX reference leaks
media: rcar-isp: Release ISPCORE resources
media: i2c: imx415: Release runtime PM reference on VBLANK error
media: i2c: imx415: Return test pattern write errors
media: renesas: vsp1: Declare index variables in for loop statement
media: renesas: vsp1: Make reset control optional to support platforms without a reset line
media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs
media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs
media: nxp: imx8-isi: Add additional 32-bit RGB format support
media: nxp: imx8-isi: Add 16-bit raw Bayer format support
media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams
media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks
media: nxp: imx8-isi: Correct color map between V4L2 and ISI
...
Diffstat (limited to 'drivers/iommu/iommu-debug-pagealloc.c')
| -rw-r--r-- | drivers/iommu/iommu-debug-pagealloc.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/drivers/iommu/iommu-debug-pagealloc.c b/drivers/iommu/iommu-debug-pagealloc.c new file mode 100644 index 000000000..80164df5b --- /dev/null +++ b/drivers/iommu/iommu-debug-pagealloc.c @@ -0,0 +1,164 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2025 - Google Inc + * Author: Mostafa Saleh <smostafa@google.com> + * IOMMU API debug page alloc sanitizer + */ +#include <linux/atomic.h> +#include <linux/iommu.h> +#include <linux/iommu-debug-pagealloc.h> +#include <linux/kernel.h> +#include <linux/page_ext.h> +#include <linux/page_owner.h> + +#include "iommu-priv.h" + +static bool needed; +DEFINE_STATIC_KEY_FALSE(iommu_debug_initialized); + +struct iommu_debug_metadata { + atomic_t ref; +}; + +static __init bool need_iommu_debug(void) +{ + return needed; +} + +struct page_ext_operations page_iommu_debug_ops = { + .size = sizeof(struct iommu_debug_metadata), + .need = need_iommu_debug, +}; + +static struct iommu_debug_metadata *get_iommu_data(struct page_ext *page_ext) +{ + return page_ext_data(page_ext, &page_iommu_debug_ops); +} + +static void iommu_debug_inc_page(phys_addr_t phys) +{ + struct page_ext *page_ext = page_ext_from_phys(phys); + struct iommu_debug_metadata *d; + + if (!page_ext) + return; + + d = get_iommu_data(page_ext); + WARN_ON(atomic_inc_return_relaxed(&d->ref) <= 0); + page_ext_put(page_ext); +} + +static void iommu_debug_dec_page(phys_addr_t phys) +{ + struct page_ext *page_ext = page_ext_from_phys(phys); + struct iommu_debug_metadata *d; + + if (!page_ext) + return; + + d = get_iommu_data(page_ext); + WARN_ON(atomic_dec_return_relaxed(&d->ref) < 0); + page_ext_put(page_ext); +} + +/* + * IOMMU page size doesn't have to match the CPU page size. So, we use + * the smallest IOMMU page size to refcount the pages in the vmemmap. + * That is important as both map and unmap has to use the same page size + * to update the refcount to avoid double counting the same page. + * And as we can't know from iommu_unmap() what was the original page size + * used for map, we just use the minimum supported one for both. + */ +static size_t iommu_debug_page_size(struct iommu_domain *domain) +{ + return 1UL << __ffs(domain->pgsize_bitmap); +} + +static bool iommu_debug_page_count(const struct page *page) +{ + unsigned int ref; + struct page_ext *page_ext = page_ext_get(page); + struct iommu_debug_metadata *d = get_iommu_data(page_ext); + + ref = atomic_read(&d->ref); + page_ext_put(page_ext); + return ref != 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; + size_t page_size = iommu_debug_page_size(domain); + + if (WARN_ON(!phys || check_add_overflow(phys, size, &end))) + return; + + for (off = 0 ; off < size ; off += page_size) + iommu_debug_inc_page(phys + off); +} + +static void __iommu_debug_update_iova(struct iommu_domain *domain, + unsigned long iova, size_t size, bool inc) +{ + size_t off, end; + size_t page_size = iommu_debug_page_size(domain); + + if (WARN_ON(check_add_overflow(iova, size, &end))) + return; + + for (off = 0 ; off < size ; off += page_size) { + phys_addr_t phys = iommu_iova_to_phys(domain, iova + off); + + if (!phys) + continue; + + if (inc) + iommu_debug_inc_page(phys); + else + iommu_debug_dec_page(phys); + } +} + +void __iommu_debug_unmap_begin(struct iommu_domain *domain, + unsigned long iova, size_t size) +{ + __iommu_debug_update_iova(domain, iova, size, false); +} + +void __iommu_debug_unmap_end(struct iommu_domain *domain, + unsigned long iova, size_t size, + size_t unmapped) +{ + if ((unmapped == size) || WARN_ON_ONCE(unmapped > size)) + return; + + /* If unmap failed, re-increment the refcount. */ + __iommu_debug_update_iova(domain, iova + unmapped, + size - unmapped, true); +} + +void iommu_debug_init(void) +{ + if (!needed) + return; + + pr_info("iommu: Debugging page allocations, expect overhead or disable iommu.debug_pagealloc"); + static_branch_enable(&iommu_debug_initialized); +} + +static int __init iommu_debug_pagealloc(char *str) +{ + return kstrtobool(str, &needed); +} +early_param("iommu.debug_pagealloc", iommu_debug_pagealloc); |
