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riscv: kexec: Avoid deadlock in kexec crash path

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If the kexec crash code is called in the interrupt context, the
machine_kexec_mask_interrupts() function will trigger a deadlock while
trying to acquire the irqdesc spinlock and then deactivate irqchip in
irq_set_irqchip_state() function.

Unlike arm64, riscv only requires irq_eoi handler to complete EOI and
keeping irq_set_irqchip_state() will only leave this possible deadlock
without any use. So we simply remove it.

Link: https://lore.kernel.org/linux-riscv/20231208111015.173237-1-songshuaishuai@tinylab.org/
Fixes: b17d19a531 ("riscv: kexec: Fixup irq controller broken in kexec crash path")
Signed-off-by: Song Shuai <songshuaishuai@tinylab.org>
Reviewed-by: Ryo Takakura <takakura@valinux.co.jp>
Link: https://lore.kernel.org/r/20240626023316.539971-1-songshuaishuai@tinylab.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This commit is contained in:
Song Shuai 2024-06-26 10:33:16 +08:00 committed by Palmer Dabbelt
parent 393da6cbb2
commit c562ba719d
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GPG key ID: 2E1319F35FBB1889
1 changed files with 1 additions and 9 deletions
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10
arch/riscv/kernel/machine_kexec.c
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@ -121,20 +121,12 @@ static void machine_kexec_mask_interrupts(void)
for_each_irq_desc(i, desc) {
struct irq_chip *chip;
int ret;
chip = irq_desc_get_chip(desc);
if (!chip)
continue;
/*
* First try to remove the active state. If this
* fails, try to EOI the interrupt.
*/
ret = irq_set_irqchip_state(i, IRQCHIP_STATE_ACTIVE, false);
if (ret && irqd_irq_inprogress(&desc->irq_data) &&
chip->irq_eoi)
if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
chip->irq_eoi(&desc->irq_data);
if (chip->irq_mask)