kernel/linux.git, branch v6.12.81

Linux 6.12.81

2026-04-11T12:24:56+00:00

Link: https://lore.kernel.org/r/20260408175927.064985309@linuxfoundation.org Tested-by: Dileep Malepu Tested-by: Shung-Hsi Yu Tested-by: Pavel Machek (CIP) Tested-by: Francesco Dolcini Tested-by: Ron Economos Tested-by: Jon Hunter Tested-by: Salvatore Bonaccorso Tested-by: Shuah Khan Link: https://lore.kernel.org/r/20260409091733.126574279@linuxfoundation.org Tested-by: Mark Brown Tested-by: Jon Hunter Tested-by: Pavel Machek (CIP) Tested-by: Florian Fainelli Tested-by: Peter Schneider Tested-by: Harshit Mogalapalli Signed-off-by: Greg Kroah-Hartman

selftests/bpf: test refining u32/s32 bounds when ranges cross min/max boundary

2026-04-11T12:24:55+00:00

[ Upstream commit f81fdfd16771e266753146bd83f6dd23515ebee9 ] Two test cases for signed/unsigned 32-bit bounds refinement when s32 range crosses the sign boundary: - s32 range [S32_MIN..1] overlapping with u32 range [3..U32_MAX], s32 range tail before sign boundary overlaps with u32 range. - s32 range [-3..5] overlapping with u32 range [0..S32_MIN+3], s32 range head after the sign boundary overlaps with u32 range. This covers both branches added in the __reg32_deduce_bounds(). Also, crossing_32_bit_signed_boundary_2() no longer triggers invariant violations. Reviewed-by: Emil Tsalapatis Reviewed-by: Paul Chaignon Acked-by: Shung-Hsi Yu Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20260306-bpf-32-bit-range-overflow-v3-2-f7f67e060a6b@gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Paul Chaignon Signed-off-by: Greg Kroah-Hartman

bpf: Fix u32/s32 bounds when ranges cross min/max boundary

2026-04-11T12:24:55+00:00

[ Upstream commit fbc7aef517d8765e4c425d2792409bb9bf2e1f13 ] Same as in __reg64_deduce_bounds(), refine s32/u32 ranges in __reg32_deduce_bounds() in the following situations: - s32 range crosses U32_MAX/0 boundary, positive part of the s32 range overlaps with u32 range: 0 U32_MAX | [xxxxxxxxxxxxxx u32 range xxxxxxxxxxxxxx] | |----------------------------|----------------------------| |xxxxx s32 range xxxxxxxxx] [xxxxxxx| 0 S32_MAX S32_MIN -1 - s32 range crosses U32_MAX/0 boundary, negative part of the s32 range overlaps with u32 range: 0 U32_MAX | [xxxxxxxxxxxxxx u32 range xxxxxxxxxxxxxx] | |----------------------------|----------------------------| |xxxxxxxxx] [xxxxxxxxxxxx s32 range | 0 S32_MAX S32_MIN -1 - No refinement if ranges overlap in two intervals. This helps for e.g. consider the following program: call %[bpf_get_prandom_u32]; w0 &= 0xffffffff; if w0 < 0x3 goto 1f; // on fall-through u32 range [3..U32_MAX] if w0 s> 0x1 goto 1f; // on fall-through s32 range [S32_MIN..1] if w0 s< 0x0 goto 1f; // range can be narrowed to [S32_MIN..-1] r10 = 0; 1: ...; The reg_bounds.c selftest is updated to incorporate identical logic, refinement based on non-overflowing range halves: ((x ∩ [0, smax]) ∩ (y ∩ [0, smax])) ∪ ((x ∩ [smin,-1]) ∩ (y ∩ [smin,-1])) Reported-by: Andrea Righi Reported-by: Emil Tsalapatis Closes: https://lore.kernel.org/bpf/aakqucg4vcujVwif@gpd4/T/ Reviewed-by: Emil Tsalapatis Acked-by: Shung-Hsi Yu Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20260306-bpf-32-bit-range-overflow-v3-1-f7f67e060a6b@gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Paul Chaignon Signed-off-by: Greg Kroah-Hartman

bpf: Add third round of bounds deduction

2026-04-11T12:24:55+00:00

[ Upstream commit 5dbb19b16ac498b0b7f3a8a85f9d25d6d8af397d ] Commit d7f008738171 ("bpf: try harder to deduce register bounds from different numeric domains") added a second call to __reg_deduce_bounds in reg_bounds_sync because a single call wasn't enough to converge to a fixed point in terms of register bounds. With patch "bpf: Improve bounds when s64 crosses sign boundary" from this series, Eduard noticed that calling __reg_deduce_bounds twice isn't enough anymore to converge. The first selftest added in "selftests/bpf: Test cross-sign 64bits range refinement" highlights the need for a third call to __reg_deduce_bounds. After instruction 7, reg_bounds_sync performs the following bounds deduction: reg_bounds_sync entry: scalar(smin=-655,smax=0xeffffeee,smin32=-783,smax32=-146) __update_reg_bounds: scalar(smin=-655,smax=0xeffffeee,smin32=-783,smax32=-146) __reg_deduce_bounds: __reg32_deduce_bounds: scalar(smin=-655,smax=0xeffffeee,smin32=-783,smax32=-146,umin32=0xfffffcf1,umax32=0xffffff6e) __reg64_deduce_bounds: scalar(smin=-655,smax=0xeffffeee,smin32=-783,smax32=-146,umin32=0xfffffcf1,umax32=0xffffff6e) __reg_deduce_mixed_bounds: scalar(smin=-655,smax=0xeffffeee,umin=umin32=0xfffffcf1,umax=0xffffffffffffff6e,smin32=-783,smax32=-146,umax32=0xffffff6e) __reg_deduce_bounds: __reg32_deduce_bounds: scalar(smin=-655,smax=0xeffffeee,umin=umin32=0xfffffcf1,umax=0xffffffffffffff6e,smin32=-783,smax32=-146,umax32=0xffffff6e) __reg64_deduce_bounds: scalar(smin=-655,smax=smax32=-146,umin=0xfffffffffffffd71,umax=0xffffffffffffff6e,smin32=-783,umin32=0xfffffcf1,umax32=0xffffff6e) __reg_deduce_mixed_bounds: scalar(smin=-655,smax=smax32=-146,umin=0xfffffffffffffd71,umax=0xffffffffffffff6e,smin32=-783,umin32=0xfffffcf1,umax32=0xffffff6e) __reg_bound_offset: scalar(smin=-655,smax=smax32=-146,umin=0xfffffffffffffd71,umax=0xffffffffffffff6e,smin32=-783,umin32=0xfffffcf1,umax32=0xffffff6e,var_off=(0xfffffffffffffc00; 0x3ff)) __update_reg_bounds: scalar(smin=-655,smax=smax32=-146,umin=0xfffffffffffffd71,umax=0xffffffffffffff6e,smin32=-783,umin32=0xfffffcf1,umax32=0xffffff6e,var_off=(0xfffffffffffffc00; 0x3ff)) In particular, notice how: 1. In the first call to __reg_deduce_bounds, __reg32_deduce_bounds learns new u32 bounds. 2. __reg64_deduce_bounds is unable to improve bounds at this point. 3. __reg_deduce_mixed_bounds derives new u64 bounds from the u32 bounds. 4. In the second call to __reg_deduce_bounds, __reg64_deduce_bounds improves the smax and umin bounds thanks to patch "bpf: Improve bounds when s64 crosses sign boundary" from this series. 5. Subsequent functions are unable to improve the ranges further (only tnums). Yet, a better smin32 bound could be learned from the smin bound. __reg32_deduce_bounds is able to improve smin32 from smin, but for that we need a third call to __reg_deduce_bounds. As discussed in [1], there may be a better way to organize the deduction rules to learn the same information with less calls to the same functions. Such an optimization requires further analysis and is orthogonal to the present patchset. Link: https://lore.kernel.org/bpf/aIKtSK9LjQXB8FLY@mail.gmail.com/ [1] Acked-by: Eduard Zingerman Co-developed-by: Eduard Zingerman Signed-off-by: Eduard Zingerman Signed-off-by: Paul Chaignon Link: https://lore.kernel.org/r/79619d3b42e5525e0e174ed534b75879a5ba15de.1753695655.git.paul.chaignon@gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Paul Chaignon Signed-off-by: Greg Kroah-Hartman

selftests/bpf: Test invariants on JSLT crossing sign

2026-04-11T12:24:55+00:00

[ Upstream commit f96841bbf4a1ee4ed0336ba192a01278fdea6383 ] The improvement of the u64/s64 range refinement fixed the invariant violation that was happening on this test for BPF_JSLT when crossing the sign boundary. After this patch, we have one test remaining with a known invariant violation. It's the same test as fixed here but for 32 bits ranges. Acked-by: Eduard Zingerman Signed-off-by: Paul Chaignon Link: https://lore.kernel.org/r/ad046fb0016428f1a33c3b81617aabf31b51183f.1753695655.git.paul.chaignon@gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Paul Chaignon Signed-off-by: Greg Kroah-Hartman

selftests/bpf: Test cross-sign 64bits range refinement

2026-04-11T12:24:55+00:00

[ Upstream commit 26e5e346a52c796190e63af1c2a80a417fda261a ] This patch adds coverage for the new cross-sign 64bits range refinement logic. The three tests cover the cases when the u64 and s64 ranges overlap (1) in the negative portion of s64, (2) in the positive portion of s64, and (3) in both portions. The first test is a simplified version of a BPF program generated by syzkaller that caused an invariant violation [1]. It looks like syzkaller could not extract the reproducer itself (and therefore didn't report it to the mailing list), but I was able to extract it from the console logs of a crash. The principle is similar to the invariant violation described in commit 6279846b9b25 ("bpf: Forget ranges when refining tnum after JSET"): the verifier walks a dead branch, uses the condition to refine ranges, and ends up with inconsistent ranges. In this case, the dead branch is when we fallthrough on both jumps. The new refinement logic improves the bounds such that the second jump is properly detected as always-taken and the verifier doesn't end up walking a dead branch. The second and third tests are inspired by the first, but rely on condition jumps to prepare the bounds instead of ALU instructions. An R10 write is used to trigger a verifier error when the bounds can't be refined. Link: https://syzkaller.appspot.com/bug?extid=c711ce17dd78e5d4fdcf [1] Acked-by: Eduard Zingerman Signed-off-by: Paul Chaignon Link: https://lore.kernel.org/r/a0e17b00dab8dabcfa6f8384e7e151186efedfdd.1753695655.git.paul.chaignon@gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Paul Chaignon Signed-off-by: Greg Kroah-Hartman

bpf: Improve bounds when s64 crosses sign boundary

2026-04-11T12:24:55+00:00

[ Upstream commit 00bf8d0c6c9be0c481fc45a3f7d87c7f8812f229 ] __reg64_deduce_bounds currently improves the s64 range using the u64 range and vice versa, but only if it doesn't cross the sign boundary. This patch improves __reg64_deduce_bounds to cover the case where the s64 range crosses the sign boundary but overlaps with the u64 range on only one end. In that case, we can improve both ranges. Consider the following example, with the s64 range crossing the sign boundary: 0 U64_MAX | [xxxxxxxxxxxxxx u64 range xxxxxxxxxxxxxx] | |----------------------------|----------------------------| |xxxxx s64 range xxxxxxxxx] [xxxxxxx| 0 S64_MAX S64_MIN -1 The u64 range overlaps only with positive portion of the s64 range. We can thus derive the following new s64 and u64 ranges. 0 U64_MAX | [xxxxxx u64 range xxxxx] | |----------------------------|----------------------------| | [xxxxxx s64 range xxxxx] | 0 S64_MAX S64_MIN -1 The same logic can probably apply to the s32/u32 ranges, but this patch doesn't implement that change. In addition to the selftests, the __reg64_deduce_bounds change was also tested with Agni, the formal verification tool for the range analysis [1]. Link: https://github.com/bpfverif/agni [1] Acked-by: Eduard Zingerman Acked-by: Shung-Hsi Yu Signed-off-by: Paul Chaignon Link: https://lore.kernel.org/r/933bd9ce1f36ded5559f92fdc09e5dbc823fa245.1753695655.git.paul.chaignon@gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Paul Chaignon Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Correct logic check error for fastboot

2026-04-11T12:24:54+00:00

[ Upstream commit b6a65009e7ce3f0cc72da18f186adb60717b51a0 ] [Why] Fix fastboot broken in driver. This is caused by an open source backport change 7495962c. from the comment, the intended check is to disable fastboot for pre-DCN10. but the logic check is reversed, and causes fastboot to be disabled on all DCN10 and after. fastboot is for driver trying to pick up bios used hw setting and bypass reprogramming the hw if dc_validate_boot_timing() condition meets. Fixes: 7495962cbceb ("drm/amd/display: Disable fastboot on DCE 6 too") Cc: stable@vger.kernel.org Reviewed-by: Mario Limonciello Reviewed-by: Ovidiu Bunea Signed-off-by: Charlene Liu Signed-off-by: Ray Wu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher Signed-off-by: Rosen Penev Signed-off-by: Greg Kroah-Hartman

drm/amd: Disable ASPM on SI

2026-04-11T12:24:54+00:00

[ Upstream commit 7bdd91abf0cb3ea78160e2e78fb58b12f6a38d55 ] Enabling ASPM causes randoms hangs on Tahiti and Oland on Zen4. It's unclear if this is a platform-specific or GPU-specific issue. Disable ASPM on SI for the time being. Reviewed-by: Alex Deucher Signed-off-by: Timur Kristóf Signed-off-by: Alex Deucher Signed-off-by: Rosen Penev Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Disable scaling on DCE6 for now

2026-04-11T12:24:54+00:00

[ Upstream commit 0e190a0446ec517666dab4691b296a9b758e590f ] Scaling doesn't work on DCE6 at the moment, the current register programming produces incorrect output when using fractional scaling (between 100-200%) on resolutions higher than 1080p. Disable it until we figure out how to program it properly. Fixes: 7c15fd86aaec ("drm/amd/display: dc/dce: add initial DCE6 support (v10)") Reviewed-by: Alex Deucher Signed-off-by: Timur Kristóf Signed-off-by: Alex Deucher Signed-off-by: Rosen Penev Signed-off-by: Greg Kroah-Hartman