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powerpc/entry: Disable interrupts before irqentry_exit

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Venkat reported a panic on powerpc-next tree where GENERIC_ENTRY has
been enabled.

kernel BUG at kernel/sched/core.c:7512!
NIP  preempt_schedule_irq+0x44/0x118
LR   dynamic_irqentry_exit_cond_resched+0x40/0x1a4
Call Trace:
 dynamic_irqentry_exit_cond_resched+0x40/0x1a4
 do_page_fault+0xc0/0x104
 data_access_common_virt+0x210/0x220

This happens since __do_page_fault ends up enabling the interrupts and
it could take significant time such that need_resched could be set. This
leads to schedule call in irqentry_exit leading to the bug.

There are many such irq handlers which enables the interrupts.
Fix it by disabling the irq before calling irqentry_exit. The same
pattern exists today in interrupt_exit_kernel_prepare.

Fixes: bee25f97ad ("powerpc: Enable GENERIC_ENTRY feature")
Reported-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Closes: https://lore.kernel.org/all/7904105b-9dfa-4efd-a5ef-bc0276ed255d@linux.ibm.com/
Signed-off-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Reviewed-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260603131054.216235-1-sshegde@linux.ibm.com
This commit is contained in:
Shrikanth Hegde 2026-06-03 18:40:54 +05:30 committed by Madhavan Srinivasan
parent 052f67a1ae
commit 334f3f6d7a
1 changed files with 3 additions and 2 deletions
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5
arch/powerpc/include/asm/entry-common.h
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@ -260,9 +260,10 @@ static inline void arch_interrupt_exit_prepare(struct pt_regs *regs)
* AMR can only have been unlocked if we interrupted the kernel.
*/
kuap_assert_locked();
local_irq_disable();
}
/* irqentry_exit expects to be called with interrupts disabled */
local_irq_disable();
}
static inline void arch_interrupt_async_enter_prepare(struct pt_regs *regs)