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Nicholas Piggin 5a9fe6b7f4 powerpc/64s: Fix local irq disable when PMIs are disabled ... commit bc88ef6632 upstream. When PMI interrupts are soft-masked, local_irq_save() will clear the PMI mask bit, allowing PMIs in and causing a race condition. This causes a deadlock in native_hpte_insert via hash_preload, which depends on PMIs being disabled since commit 8b91cee5ea ("powerpc/64s/hash: Make hash faults work in NMI context"). native_hpte_insert calls local_irq_save(). It's possible the lpar hash code is also affected when tracing is enabled because __trace_hcall_entry() calls local_irq_save(). Fix this by making arch_local_irq_save() _or_ the IRQS_DISABLED bit into the mask. This was found with the stress_hpt option with a kbuild workload running together with `perf record -g`. Fixes: f442d00480 ("powerpc/64s: Add support to mask perf interrupts and replay them") Fixes: 8b91cee5ea ("powerpc/64s/hash: Make hash faults work in NMI context") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Just take the fix without the new warning] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230121095352.2823517-1-npiggin@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		History 2023-02-09 11:28:26 +01:00
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asm	powerpc/64s: Fix local irq disable when PMIs are disabled	2023-02-09 11:28:26 +01:00
uapi/asm	powerpc/bpf: Fix use of user_pt_regs in uapi	2022-06-29 20:43:04 +10:00