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Guo Ren 69ea463021 irqchip/sifive-plic: Fixup EOI failed when masked
When using "devm_request_threaded_irq(,,,,IRQF_ONESHOT,,)" in a driver,
only the first interrupt is handled, and following interrupts are never
delivered (initially reported in [1]).

That's because the RISC-V PLIC cannot EOI masked interrupts, as explained
in the description of Interrupt Completion in the PLIC spec [2]:

<quote>
The PLIC signals it has completed executing an interrupt handler by
writing the interrupt ID it received from the claim to the claim/complete
register. The PLIC does not check whether the completion ID is the same
as the last claim ID for that target. If the completion ID does not match
an interrupt source that *is currently enabled* for the target, the
completion is silently ignored.
</quote>

Re-enable the interrupt before completion if it has been masked during
the handling, and remask it afterwards.

[1] http://lists.infradead.org/pipermail/linux-riscv/2021-July/007441.html
[2] 8bc15a35d0/riscv-plic.adoc

Fixes: bb0fed1c60 ("irqchip/sifive-plic: Switch to fasteoi flow")
Reported-by: Vincent Pelletier <plr.vincent@gmail.com>
Tested-by: Nikita Shubin <nikita.shubin@maquefel.me>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: stable@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
[maz: amended commit message]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211105094748.3894453-1-guoren@kernel.org
2021-11-12 16:09:51 +00:00
arch Merge branch 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2021-11-10 16:15:54 -08:00
block for-5.16/drivers-2021-11-09 2021-11-09 11:24:08 -08:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto Kbuild updates for v5.16 2021-11-08 09:15:45 -08:00
Documentation A slow cycle for nfsd: mainly cleanup, including Neil's patch dropping 2021-11-10 16:45:54 -08:00
drivers irqchip/sifive-plic: Fixup EOI failed when masked 2021-11-12 16:09:51 +00:00
fs Only bug fixes and cleanups for ext4 this merge window. Of note are 2021-11-10 17:05:37 -08:00
include A slow cycle for nfsd: mainly cleanup, including Neil's patch dropping 2021-11-10 16:45:54 -08:00
init Merge branch 'akpm' (patches from Andrew) 2021-11-09 10:11:53 -08:00
ipc ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL 2021-11-09 10:02:53 -08:00
kernel Merge branch 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2021-11-10 16:15:54 -08:00
lib Merge branch 'akpm' (patches from Andrew) 2021-11-09 10:11:53 -08:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm pidfd.v5.16 2021-11-10 16:02:08 -08:00
net A slow cycle for nfsd: mainly cleanup, including Neil's patch dropping 2021-11-10 16:45:54 -08:00
samples Add gitignore file for samples/fanotify/ subdirectory 2021-11-07 11:19:24 -08:00
scripts Merge branch 'akpm' (patches from Andrew) 2021-11-09 10:11:53 -08:00
security Merge branch 'akpm' (patches from Andrew) 2021-11-06 14:08:17 -07:00
sound TTY / Serial driver update for 5.16-rc1 2021-11-04 09:09:37 -07:00
tools arm64 fixes for -rc1 2021-11-10 11:29:30 -08:00
usr initramfs: Check timestamp to prevent broken cpio archive 2021-10-24 13:48:40 +09:00
virt kvm: irqfd: avoid update unmodified entries of the routing 2021-09-30 04:27:10 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
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.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap Merge branch 'akpm' (patches from Andrew) 2021-11-09 10:11:53 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS chrome platform changes for 5.16 2021-11-10 11:36:43 -08:00
Makefile Kbuild updates for v5.16 2021-11-08 09:15:45 -08:00
README

Linux kernel
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