Description
In the Linux kernel, the following vulnerability has been resolved: firmware: arm_sdei: Fix sleep from invalid context BUG Running a preempt-rt (v6.2-rc3-rt1) based kernel on an Ampere Altra triggers: BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46 in_atomic(): 0, irqs_disabled(): 128, non_block: 0, pid: 24, name: cpuhp/0 preempt_count: 0, expected: 0 RCU nest depth: 0, expected: 0 3 locks held by cpuhp/0/24: #0: ffffda30217c70d0 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x5c/0x248 #1: ffffda30217c7120 (cpuhp_state-up){+.+.}-{0:0}, at: cpuhp_thread_fun+0x5c/0x248 #2: ffffda3021c711f0 (sdei_list_lock){....}-{3:3}, at: sdei_cpuhp_up+0x3c/0x130 irq event stamp: 36 hardirqs last enabled at (35): [<ffffda301e85b7bc>] finish_task_switch+0xb4/0x2b0 hardirqs last disabled at (36): [<ffffda301e812fec>] cpuhp_thread_fun+0x21c/0x248 softirqs last enabled at (0): [<ffffda301e80b184>] copy_process+0x63c/0x1ac0 softirqs last disabled at (0): [<0000000000000000>] 0x0 CPU: 0 PID: 24 Comm: cpuhp/0 Not tainted 5.19.0-rc3-rt5-[...] Hardware name: WIWYNN Mt.Jade Server [...] Call trace: dump_backtrace+0x114/0x120 show_stack+0x20/0x70 dump_stack_lvl+0x9c/0xd8 dump_stack+0x18/0x34 __might_resched+0x188/0x228 rt_spin_lock+0x70/0x120 sdei_cpuhp_up+0x3c/0x130 cpuhp_invoke_callback+0x250/0xf08 cpuhp_thread_fun+0x120/0x248 smpboot_thread_fn+0x280/0x320 kthread+0x130/0x140 ret_from_fork+0x10/0x20 sdei_cpuhp_up() is called in the STARTING hotplug section, which runs with interrupts disabled. Use a CPUHP_AP_ONLINE_DYN entry instead to execute the cpuhp cb later, with preemption enabled. SDEI originally got its own cpuhp slot to allow interacting with perf. It got superseded by pNMI and this early slot is not relevant anymore. [1] Some SDEI calls (e.g. SDEI_1_0_FN_SDEI_PE_MASK) take actions on the calling CPU. It is checked that preemption is disabled for them. _ONLINE cpuhp cb are executed in the 'per CPU hotplug thread'. Preemption is enabled in those threads, but their cpumask is limited to 1 CPU. Move 'WARN_ON_ONCE(preemptible())' statements so that SDEI cpuhp cb don't trigger them. Also add a check for the SDEI_1_0_FN_SDEI_PRIVATE_RESET SDEI call which acts on the calling CPU. [1]: https://lore.kernel.org/all/5813b8c5-ae3e-87fd-fccc-94c9cd08816d@arm.com/
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
f92b5462a2f22d13a75dc663f7b2fac16a3e61cb to < 59842a9ba27d5390ae5bf3233a92cad3a26d495caffectedf92b5462a2f22d13a75dc663f7b2fac16a3e61cb to < 48ac727ea4a3577eb1b4e24f807ba532c47930f9affectedf92b5462a2f22d13a75dc663f7b2fac16a3e61cb to < 7d8f5ccc826b39e05ff252b1fccd808c7a0725e0affectedf92b5462a2f22d13a75dc663f7b2fac16a3e61cb to < 66caf22787714c925e755719c293aaf3cb0b873baffectedf92b5462a2f22d13a75dc663f7b2fac16a3e61cb to < a8267bc8de736cae927165191b52fbc20d101dd1affectedf92b5462a2f22d13a75dc663f7b2fac16a3e61cb to < 18d5ea5b746120a3972e6c347ad9428228445327affectedf92b5462a2f22d13a75dc663f7b2fac16a3e61cb to < d2c48b2387eb89e0bf2a2e06e30987cf410acad4affected
Linux Linux
Default version status: affected
4.16affected0 to < 4.16unaffected4.19.284 to ≤ 4.19.*unaffected5.4.244 to ≤ 5.4.*unaffected5.10.181 to ≤ 5.10.*unaffected5.15.113 to ≤ 5.15.*unaffected6.1.30 to ≤ 6.1.*unaffected6.3.4 to ≤ 6.3.*unaffected6.4 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/59842a9ba27d5390ae5bf3233a92cad3a26d495c ↗
- https://git.kernel.org/stable/c/48ac727ea4a3577eb1b4e24f807ba532c47930f9 ↗
- https://git.kernel.org/stable/c/7d8f5ccc826b39e05ff252b1fccd808c7a0725e0 ↗
- https://git.kernel.org/stable/c/66caf22787714c925e755719c293aaf3cb0b873b ↗
- https://git.kernel.org/stable/c/a8267bc8de736cae927165191b52fbc20d101dd1 ↗
- https://git.kernel.org/stable/c/18d5ea5b746120a3972e6c347ad9428228445327 ↗
- https://git.kernel.org/stable/c/d2c48b2387eb89e0bf2a2e06e30987cf410acad4 ↗