kernel/linux.git/drivers/gpu/drm/drm_panic.c, branch v6.19.11

drm/panic: Fix 24bit pixel crossing page boundaries

2025-10-21T09:28:03+00:00

When using page list framebuffer, and using RGB888 format, some pixels can cross the page boundaries, and this case was not handled, leading to writing 1 or 2 bytes on the next virtual address. Add a check and a specific function to handle this case. Fixes: c9ff2808790f0 ("drm/panic: Add support to scanout buffer as array of pages") Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20251009122955.562888-7-jfalempe@redhat.com Signed-off-by: Jocelyn Falempe

drm/panic: Fix divide by 0 if the screen width < font width

2025-10-21T09:28:03+00:00

In the unlikely case that the screen is tiny, and smaller than the font width, it leads to a divide by 0: draw_line_with_wrap() chars_per_row = sb->width / font->width = 0 line_wrap.len = line->len % chars_per_row; This will trigger a divide by 0 Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20251009122955.562888-6-jfalempe@redhat.com Signed-off-by: Jocelyn Falempe

drm/panic: Fix kmsg text drawing rectangle

2025-10-21T09:28:03+00:00

The rectangle height was larger than the screen size. This has no real impact. Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20251009122955.562888-5-jfalempe@redhat.com Signed-off-by: Jocelyn Falempe

drm/panic: Fix qr_code, ensure vmargin is positive

2025-10-21T09:28:03+00:00

Depending on qr_code size and screen size, the vertical margin can be negative, that means there is not enough room to draw the qr_code. So abort early, to avoid a segfault by trying to draw at negative coordinates. Fixes: cb5164ac43d0f ("drm/panic: Add a QR code panic screen") Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20251009122955.562888-4-jfalempe@redhat.com Signed-off-by: Jocelyn Falempe

drm/panic: Fix overlap between qr code and logo

2025-10-21T09:28:02+00:00

The borders of the qr code was not taken into account to check if it overlap with the logo, leading to the logo being partially covered. Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20251009122955.562888-3-jfalempe@redhat.com Signed-off-by: Jocelyn Falempe

drm/panic: Fix drawing the logo on a small narrow screen

2025-10-21T09:28:02+00:00

If the logo width is bigger than the framebuffer width, and the height is big enough to hold the logo and the message, it will draw at x coordinate that are higher than the width, and ends up in a corrupted image. Fixes: 4b570ac2eb54 ("drm/rect: Add drm_rect_overlap()") Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20251009122955.562888-2-jfalempe@redhat.com Signed-off-by: Jocelyn Falempe

drm: Include

2025-06-16T07:01:23+00:00

Fix the compile-time warnings drivers/gpu/drm/drm_atomic.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_atomic_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_atomic_state_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_atomic_uapi.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_auth.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_buddy.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_color_mgmt.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_connector.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_damage_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_debugfs_crc.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_drv.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_edid.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_exec.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_fb_dma_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_file.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_flip_work.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_format_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_gpusvm.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_gpuvm.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_managed.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_mipi_dbi.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_mipi_dsi.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_mode_config.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_modeset_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_modeset_lock.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_panic.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_plane.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_plane_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_print.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_privacy_screen.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_self_refresh_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_simple_kms_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_suballoc.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_syncobj.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_vblank_work.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_vma_manager.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_writeback.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/lib/drm_random.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/tests/drm_kunit_helpers.c: warning: EXPORT_SYMBOL() is used, but #include is missing Signed-off-by: Thomas Zimmermann Fixes: a934a57a42f6 ("scripts/misc-check: check missing #include when W=1") Reviewed-by: André Almeida Cc: Masahiro Yamada Cc: Nathan Chancellor Link: https://lore.kernel.org/r/20250612121633.229222-3-tzimmermann@suse.de

drm/panic: Add support to scanout buffer as array of pages

2025-04-10T08:50:58+00:00

Some drivers like virtio-gpu, don't map the scanout buffer in the kernel. Calling vmap() in a panic handler is not safe, and writing an atomic_vmap() API is more complex than expected [1]. So instead, pass the array of pages of the scanout buffer to the panic handler, and map only one page at a time to draw the pixels. This is obviously slow, but acceptable for a panic handler. [1] https://lore.kernel.org/dri-devel/20250305152555.318159-1-ryasuoka@redhat.com/ Acked-by: Thomas Zimmermann Acked-by: Simona Vetter Signed-off-by: Jocelyn Falempe Link: https://lore.kernel.org/r/20250407140138.162383-3-jfalempe@redhat.com

Merge tag 'rust-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux

2025-03-31T00:03:26+00:00

Pull Rust updates from Miguel Ojeda: "Toolchain and infrastructure: - Extract the 'pin-init' API from the 'kernel' crate and make it into a standalone crate. In order to do this, the contents are rearranged so that they can easily be kept in sync with the version maintained out-of-tree that other projects have started to use too (or plan to, like QEMU). This will reduce the maintenance burden for Benno, who will now have his own sub-tree, and will simplify future expected changes like the move to use 'syn' to simplify the implementation. - Add '#[test]'-like support based on KUnit. We already had doctests support based on KUnit, which takes the examples in our Rust documentation and runs them under KUnit. Now, we are adding the beginning of the support for "normal" tests, similar to those the '#[test]' tests in userspace Rust. For instance: #[kunit_tests(my_suite)] mod tests { #[test] fn my_test() { assert_eq!(1 + 1, 2); } } Unlike with doctests, the 'assert*!'s do not map to the KUnit assertion APIs yet. - Check Rust signatures at compile time for functions called from C by name. In particular, introduce a new '#[export]' macro that can be placed in the Rust function definition. It will ensure that the function declaration on the C side matches the signature on the Rust function: #[export] pub unsafe extern "C" fn my_function(a: u8, b: i32) -> usize { // ... } The macro essentially forces the compiler to compare the types of the actual Rust function and the 'bindgen'-processed C signature. These cases are rare so far. In the future, we may consider introducing another tool, 'cbindgen', to generate C headers automatically. Even then, having these functions explicitly marked may be a good idea anyway. - Enable the 'raw_ref_op' Rust feature: it is already stable, and allows us to use the new '&raw' syntax, avoiding a couple macros. After everyone has migrated, we will disallow the macros. - Pass the correct target to 'bindgen' on Usermode Linux. - Fix 'rusttest' build in macOS. 'kernel' crate: - New 'hrtimer' module: add support for setting up intrusive timers without allocating when starting the timer. Add support for 'Pin>', 'Arc<_>', 'Pin<&_>' and 'Pin<&mut _>' as pointer types for use with timer callbacks. Add support for setting clock source and timer mode. - New 'dma' module: add a simple DMA coherent allocator abstraction and a test sample driver. - 'list' module: make the linked list 'Cursor' point between elements, rather than at an element, which is more convenient to us and allows for cursors to empty lists; and document it with examples of how to perform common operations with the provided methods. - 'str' module: implement a few traits for 'BStr' as well as the 'strip_prefix()' method. - 'sync' module: add 'Arc::as_ptr'. - 'alloc' module: add 'Box::into_pin'. - 'error' module: extend the 'Result' documentation, including a few examples on different ways of handling errors, a warning about using methods that may panic, and links to external documentation. 'macros' crate: - 'module' macro: add the 'authors' key to support multiple authors. The original key will be kept until everyone has migrated. Documentation: - Add error handling sections. MAINTAINERS: - Add Danilo Krummrich as reviewer of the Rust "subsystem". - Add 'RUST [PIN-INIT]' entry with Benno Lossin as maintainer. It has its own sub-tree. - Add sub-tree for 'RUST [ALLOC]'. - Add 'DMA MAPPING HELPERS DEVICE DRIVER API [RUST]' entry with Abdiel Janulgue as primary maintainer. It will go through the sub-tree of the 'RUST [ALLOC]' entry. - Add 'HIGH-RESOLUTION TIMERS [RUST]' entry with Andreas Hindborg as maintainer. It has its own sub-tree. And a few other cleanups and improvements" * tag 'rust-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (71 commits) rust: dma: add `Send` implementation for `CoherentAllocation` rust: macros: fix `make rusttest` build on macOS rust: block: refactor to use `&raw mut` rust: enable `raw_ref_op` feature rust: uaccess: name the correct function rust: rbtree: fix comments referring to Box instead of KBox rust: hrtimer: add maintainer entry rust: hrtimer: add clocksource selection through `ClockId` rust: hrtimer: add `HrTimerMode` rust: hrtimer: implement `HrTimerPointer` for `Pin>` rust: alloc: add `Box::into_pin` rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&mut T>` rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&T>` rust: hrtimer: add `hrtimer::ScopedHrTimerPointer` rust: hrtimer: add `UnsafeHrTimerPointer` rust: hrtimer: allow timer restart from timer handler rust: str: implement `strip_prefix` for `BStr` rust: str: implement `AsRef` for `[u8]` and `BStr` rust: str: implement `Index` for `BStr` rust: str: implement `PartialEq` for `BStr` ...

panic_qr: use new #[export] macro

2025-03-09T19:52:46+00:00

This validates at compile time that the signatures match what is in the header file. It highlights one annoyance with the compile-time check, which is that it can only be used with functions marked unsafe. If the function is not unsafe, then this error is emitted: error[E0308]: `if` and `else` have incompatible types --> /drivers/gpu/drm/drm_panic_qr.rs:987:19 | 986 | #[export] | --------- expected because of this 987 | pub extern "C" fn drm_panic_qr_max_data_size(version: u8, url_len: usize) -> usize { | ^^^^^^^^^^^^^^^^^^^^^^^^^^ expected unsafe fn, found safe fn | = note: expected fn item `unsafe extern "C" fn(_, _) -> _ {kernel::bindings::drm_panic_qr_max_data_size}` found fn item `extern "C" fn(_, _) -> _ {drm_panic_qr_max_data_size}` The signature declarations are moved to a header file so it can be included in the Rust bindings helper, and the extern keyword is removed as it is unnecessary. Reviewed-by: Andreas Hindborg Reviewed-by: Tamir Duberstein Acked-by: Simona Vetter Acked-by: Greg Kroah-Hartman Signed-off-by: Alice Ryhl Reviewed-by: Jocelyn Falempe Link: https://lore.kernel.org/r/20250303-export-macro-v3-5-41fbad85a27f@google.com [ Fixed `rustfmt`. Moved on top the unsafe requirement comment to follow the usual style, and slightly reworded it for clarity. Formatted bindings helper comment. - Miguel ] Signed-off-by: Miguel Ojeda