kernel/linux.git, branch v6.12.79

Linux 6.12.79

2026-03-27T09:52:52+00:00

Signed-off-by: Greg Kroah-Hartman

Revert "LoongArch: Add machine_kexec_mask_interrupts() implementation"

2026-03-27T09:52:52+00:00

This reverts commit 429bf3f04c24a1590ed18cd7bf802cf63f937a0f. 6.12.78 backported "kexec: Consolidate machine_kexec_mask_interrupts() implementation" so the arch-specific implementation is redundant. Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

Linux 6.12.78

2026-03-25T10:08:58+00:00

Link: https://lore.kernel.org/r/20260323134526.647552166@linuxfoundation.org Tested-by: Brett A C Sheffield Tested-by: Peter Schneider Tested-by: Pavel Machek (CIP) Tested-by: Florian Fainelli Tested-by: Salvatore Bonaccorso Tested-by: Shuah Khan Tested-by: Harshit Mogalapalli Tested-by: Ron Economos Tested-by: Francesco Dolcini Tested-by: Jon Hunter Tested-by: Mark Brown Tested-by: Barry K. Nathan Signed-off-by: Greg Kroah-Hartman

xen/privcmd: add boot control for restricted usage in domU

2026-03-25T10:08:57+00:00

commit 1613462be621ad5103ec338a7b0ca0746ec4e5f1 upstream. When running in an unprivileged domU under Xen, the privcmd driver is restricted to allow only hypercalls against a target domain, for which the current domU is acting as a device model. Add a boot parameter "unrestricted" to allow all hypercalls (the hypervisor will still refuse destructive hypercalls affecting other guests). Make this new parameter effective only in case the domU wasn't started using secure boot, as otherwise hypercalls targeting the domU itself might result in violating the secure boot functionality. This is achieved by adding another lockdown reason, which can be tested to not being set when applying the "unrestricted" option. This is part of XSA-482 Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman

xen/privcmd: restrict usage in unprivileged domU

2026-03-25T10:08:57+00:00

commit 453b8fb68f3641fea970db88b7d9a153ed2a37e8 upstream. The Xen privcmd driver allows to issue arbitrary hypercalls from user space processes. This is normally no problem, as access is usually limited to root and the hypervisor will deny any hypercalls affecting other domains. In case the guest is booted using secure boot, however, the privcmd driver would be enabling a root user process to modify e.g. kernel memory contents, thus breaking the secure boot feature. The only known case where an unprivileged domU is really needing to use the privcmd driver is the case when it is acting as the device model for another guest. In this case all hypercalls issued via the privcmd driver will target that other guest. Fortunately the privcmd driver can already be locked down to allow only hypercalls targeting a specific domain, but this mode can be activated from user land only today. The target domain can be obtained from Xenstore, so when not running in dom0 restrict the privcmd driver to that target domain from the beginning, resolving the potential problem of breaking secure boot. This is XSA-482 Reported-by: Teddy Astie Fixes: 1c5de1939c20 ("xen: add privcmd driver") Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman

perf/x86/intel: Add missing branch counters constraint apply

2026-03-25T10:08:57+00:00

[ Upstream commit 1d07bbd7ea36ea0b8dfa8068dbe67eb3a32d9590 ] When running the command: 'perf record -e "{instructions,instructions:p}" -j any,counter sleep 1', a "shift-out-of-bounds" warning is reported on CWF. UBSAN: shift-out-of-bounds in /kbuild/src/consumer/arch/x86/events/intel/lbr.c:970:15 shift exponent 64 is too large for 64-bit type 'long long unsigned int' ...... intel_pmu_lbr_counters_reorder.isra.0.cold+0x2a/0xa7 intel_pmu_lbr_save_brstack+0xc0/0x4c0 setup_arch_pebs_sample_data+0x114b/0x2400 The warning occurs because the second "instructions:p" event, which involves branch counters sampling, is incorrectly programmed to fixed counter 0 instead of the general-purpose (GP) counters 0-3 that support branch counters sampling. Currently only GP counters 0-3 support branch counters sampling on CWF, any event involving branch counters sampling should be programed on GP counters 0-3. Since the counter index of fixed counter 0 is 32, it leads to the "src" value in below code is right shifted 64 bits and trigger the "shift-out-of-bounds" warning. cnt = (src >> (order[j] * LBR_INFO_BR_CNTR_BITS)) & LBR_INFO_BR_CNTR_MASK; The root cause is the loss of the branch counters constraint for the new event in the branch counters sampling event group. Since it isn't yet part of the sibling list. This results in the second "instructions:p" event being programmed on fixed counter 0 incorrectly instead of the appropriate GP counters 0-3. To address this, we apply the missing branch counters constraint for the last event in the group. Additionally, we introduce a new function, `intel_set_branch_counter_constr()`, to apply the branch counters constraint and avoid code duplication. Fixes: 33744916196b ("perf/x86/intel: Support branch counters logging") Reported-by: Xudong Hao Signed-off-by: Dapeng Mi Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20260228053320.140406-2-dapeng1.mi@linux.intel.com Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

hwmon: (max6639) Fix pulses-per-revolution implementation

2026-03-25T10:08:57+00:00

[ Upstream commit e7bae9a7a5e1251ab414291f4e9304d702bb9221 ] The valid range for the pulses-per-revolution devicetree property is 1..4. The current code checks for a range of 1..5. Fix it. Declare the variable used to retrieve pulses per revolution from devicetree as u32 (unsigned) to match the of_property_read_u32() API. The current code uses a postfix decrement when writing the pulses per resolution into the chip. This has no effect since the value is evaluated before it is decremented. Fix it by decrementing before evaluating the value. Fixes: 7506ebcd662b ("hwmon: (max6639) : Configure based on DT property") Cc: Naresh Solanki Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin

tools/bootconfig: fix fd leak in load_xbc_file() on fstat failure

2026-03-25T10:08:57+00:00

[ Upstream commit 3b2c2ab4ceb82af484310c3087541eab00ea288b ] If fstat() fails after open() succeeds, the function returns without closing the file descriptor. Also preserve errno across close(), since close() may overwrite it before the error is returned. Link: https://lore.kernel.org/all/20260318155847.78065-3-objecting@objecting.org/ Fixes: 950313ebf79c ("tools: bootconfig: Add bootconfig command") Signed-off-by: Josh Law Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Sasha Levin

lib/bootconfig: check xbc_init_node() return in override path

2026-03-25T10:08:57+00:00

[ Upstream commit bb288d7d869e86d382f35a0e26242c5ccb05ca82 ] The ':=' override path in xbc_parse_kv() calls xbc_init_node() to re-initialize an existing value node but does not check the return value. If xbc_init_node() fails (data offset out of range), parsing silently continues with stale node data. Add the missing error check to match the xbc_add_node() call path which already checks for failure. In practice, a bootconfig using ':=' to override a value near the 32KB data limit could silently retain the old value, meaning a security-relevant boot parameter override (e.g., a trace filter or debug setting) would not take effect as intended. Link: https://lore.kernel.org/all/20260318155847.78065-2-objecting@objecting.org/ Fixes: e5efaeb8a8f5 ("bootconfig: Support mixing a value and subkeys under a key") Signed-off-by: Josh Law Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Sasha Levin

fs/tests: exec: Remove bad test vector

2026-03-25T10:08:57+00:00

[ Upstream commit c4192754e836e0ffed95833509b6ada975b74418 ] Drop an unusable test in the bprm stack limits. Reported-by: Guenter Roeck Closes: https://lore.kernel.org/all/a3e9b1c2-40c1-45df-9fa2-14ee6a7b3fe2@roeck-us.net Fixes: 60371f43e56b ("exec: Add KUnit test for bprm_stack_limits()") Signed-off-by: Kees Cook Signed-off-by: Sasha Levin