From: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> mainline inclusion from mainline-v7.1-rc4 commit 183182235f6d53bac62c6c39014738a54a68dfa6 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/15974 CVE: CVE-2026-53285 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- [Why] dcn32_validate_bandwidth() wraps dcn32_internal_validate_bw() with DC_FP_START()/DC_FP_END(). In x86 non-RT, DC_FP_START takes fpregs_lock(), which disables local softirqs. The DML1 path through dcn32_enable_phantom_plane() calls kvzalloc() to allocate ~335 KiB for dc_plane_state. This triggers the vmalloc path, which calls BUG_ON(in_interrupt()) because it's invoked within the FPU-enabled (softirq disabled) region, leading to a kernel crash. [How] Wrap the dc_state_create_phantom_plane() call with the DC_RUN_WITH_PREEMPTION_ENABLED() macro to allow preemption during this memory allocation. Fixes: 235c67634230 ("drm/amd/display: add DCN32/321 specific files for Display Core") Closes: https://gitlab.freedesktop.org/drm/amd/-/work_items/4470 Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com> Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Signed-off-by: James Lin <pinglei.lin@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 885ccbef7b94a8b38f69c4211c679021aa27ad11) Cc: stable@vger.kernel.org Conflicts: drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c [context conflicts.] Signed-off-by: Jiacheng Yu <yujiacheng3@huawei.com> --- .../gpu/drm/amd/display/dc/dcn32/dcn32_resource.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c index ab6b4f44f537..3d30608e98e7 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c +++ b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c @@ -89,6 +89,15 @@ #include "dcn20/dcn20_vmid.h" #include "dml/dcn32/dcn32_fpu.h" +#include "dc_state_priv.h" +#include "dc_fpu.h" + +#include "dml2_0/dml2_wrapper.h" + +#if !defined(DC_RUN_WITH_PREEMPTION_ENABLED) +#define DC_RUN_WITH_PREEMPTION_ENABLED(code) code +#endif + #define DC_LOGGER_INIT(logger) enum dcn32_clk_src_array_id { @@ -1643,7 +1652,8 @@ static void dcn32_enable_phantom_plane(struct dc *dc, if (curr_pipe->top_pipe && curr_pipe->top_pipe->plane_state == curr_pipe->plane_state) phantom_plane = prev_phantom_plane; else - phantom_plane = dc_create_plane_state(dc); + DC_RUN_WITH_PREEMPTION_ENABLED(phantom_plane = + dc_create_plane_state(dc)); if (!phantom_plane) continue; -- 2.34.1