From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794047905; b=vdk2kamR3kUI85xZnU5arDp2AHiUh/amTriL/fRL0tWwGufLUjz4u4IQjd8OF7puMhXu Hk/Dbz80YX8id3DiWj1twohzfxH14nV2pCm1zmjZr5UdQrnFu9fyrP5AMkb4p0Vaqyzzm EAQg+vqKXrRAddSaOffHkq3yxJowK4vIxBoQ6ur1xiEQS4vWR6hq8unoq9NS6ZNQf2NbI vdflva+GzpPGZKP9GmiO728I59XAJVAhDxq0S93Xg5iUyAeFRgxG9oE8B+p+GhlXTDlJC 1zYBLv1aOSzo8d4bD5dmyGKDm3DH7VwRYf6RuwaAZB+OyQPi3MHkAleU0m65BywuGZg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794047905; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=66QbGKaaLlZDAv0xzTAeFfq01iyFXQ5G9W5VgVWuUAA=; b=H7q7czNQFmz5FSzGk+ELR46e3a3hw6zmIhgzHBlR8J/YLJJvX5DMv8esagdeH+RMuyrW R7aKkKOVGxCibrJRXKW/0Jw9D4zWcB3QnhJFj9wBf4o5up6L16OLkZWub5W8Cmgn1y6TB w24WX5t5vtI/riAl4mRu66OlVWHq4xpMv81ls/DBYKlwrYMgvgEcvBRgI9QB2PRlHQVHG qJs/6iOyrLX+193XrJqasOYLy/i/uy72MLMNqQZg9/zN9n6Oziazk3+QtnoSccljrdRno NEcNru2N8Yi0TSfHLLPlmdMlXvrq1C4BMDFtTZL2kg/1eBONVQF26aOzeaXMOosZepQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=U5HrB+sF; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CDC31606A326 for ; Sat, 7 Nov 2026 10:38:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=U5HrB+sF Received: by smtp.kernel.org (Postfix) with ESMTPSA id 49E031F0089F; Sat, 7 Nov 2026 10:38:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794047904; bh=66QbGKaaLlZDAv0xzTAeFfq01iyFXQ5G9W5VgVWuUAA=; h=From:To:Cc:Subject:Date; b=U5HrB+sFPSiP0osC61MGq2ilvuXNULWPnWEmUB+hLfKpwdX4dukbxW4x17YATUJA+ pbTaKNR0S59pl6sOy92hoFWid5wDImN1Bmkuhs0JJ1OEVkMCIXRAvoRfq8o/iZsHtr A8e5LEXnB4yL/RHx5fupSYr0Ei/yoXVBixpU2iZ1b4emow/OrMioTznDFNOBEsjXa0 g6DLrayN5JGR6SEnQZ3G4+/7ykkXDZlARMpb4+7w52d3UZXUzoOn1vdVf3Z8PrBETa P3EpSS2vDzC06gl36syhPZQCTQwLAV2zmHsNxJhGWMjowGXsIjyqt/U0QXxwV03LSL 0EuVDBGfu0tVw== From: Sasha Levin To: iav@iav.lv, tglx@kernel.org Cc: stable@vger.kernel.org Subject: FAILED: patch "[PATCH] genirq/kexec: Do not take the bus lock of an interrupt chip on the crash path" failed to apply to 6.6-stable tree Date: Sat, 7 Nov 2026 05:38:23 -0500 Message-ID: <20261107053823-failed-6.6-717862eac6ef@kernel.org> X-Mailer: git-send-email 2.53.0 X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 717862eac6eff0eea8ac30a0c0de0bed84922aab # git commit -s git send-email --to '' --in-reply-to '20261107053823-failed-6.6-717862eac6ef@kernel.org' --subject-prefix 'PATCH 6.6.y' 'HEAD^..' Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From 717862eac6eff0eea8ac30a0c0de0bed84922aab Mon Sep 17 00:00:00 2001 From: Igor Velkov Date: Thu, 15 Oct 2026 21:51:50 +0300 Subject: [PATCH] genirq/kexec: Do not take the bus lock of an interrupt chip on the crash path machine_kexec_mask_interrupts() calls irq_set_irqchip_state() for every started interrupt. That function takes the bus lock of the chip and desc->lock, and syncs the chip when it drops them. On the crash path interrupts are off and the other CPUs are stopped, so a chip whose bus transfer is completed by an interrupt never returns from the sync. On RK3399 boards with an RK808 PMIC the RTC alarm interrupt belongs to the regmap-irq chip of the RK808, which sits on I2C. rk808_irq_chip sets init_ack_masked, so regmap_irq_sync_unlock() writes the ack register on every unlock, and the I2C controller needs its own interrupt to finish the transfer. A panic with a crash kernel loaded prints SMP: stopping secondary CPUs and then nothing until the watchdog resets the board. machine_kexec_mask_interrupts() takes neither lock for the other operations on the descriptor. Move the search for the chip that implements irq_set_irqchip_state() into __irq_set_irqchip_state(), which takes no locks, and call it from machine_kexec_mask_interrupts(). Fixes: 78fd584cdec0 ("arm64: kdump: implement machine_crash_shutdown()") Suggested-by: Thomas Gleixner Signed-off-by: Igor Velkov Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20261015-kexec-irq-bus-lock-v2-1-2af15f0757b6@iav.lv --- kernel/irq/internals.h | 1 + kernel/irq/kexec.c | 2 +- kernel/irq/manage.c | 43 +++++++++++++++++++++++------------------- 3 files changed, 26 insertions(+), 20 deletions(-) diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index 0ce21dd454047..4dff3ccae1812 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -81,6 +81,7 @@ enum { #include "settings.h" extern int __irq_set_trigger(struct irq_desc *desc, unsigned long flags); +extern int __irq_set_irqchip_state(struct irq_desc *desc, enum irqchip_irq_state which, bool val); extern void __disable_irq(struct irq_desc *desc); extern void __enable_irq(struct irq_desc *desc); diff --git a/kernel/irq/kexec.c b/kernel/irq/kexec.c index 1a3deffe6b5b6..f245b98764225 100644 --- a/kernel/irq/kexec.c +++ b/kernel/irq/kexec.c @@ -25,7 +25,7 @@ void machine_kexec_mask_interrupts(void) * First try to remove the active state from an interrupt which is forwarded * to a VM. If the interrupt is not forwarded, try to EOI the interrupt. */ - check_eoi = irq_set_irqchip_state(i, IRQCHIP_STATE_ACTIVE, false); + check_eoi = __irq_set_irqchip_state(desc, IRQCHIP_STATE_ACTIVE, false); } if (check_eoi && chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data)) diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 57eff26fa646a..bdb47837c66fc 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -2735,6 +2735,28 @@ int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which, bool * } EXPORT_SYMBOL_GPL(irq_get_irqchip_state); +int __irq_set_irqchip_state(struct irq_desc *desc, enum irqchip_irq_state which, bool val) +{ + struct irq_data *data = irq_desc_get_irq_data(desc); + struct irq_chip *chip; + + do { + chip = irq_data_get_irq_chip(data); + + if (WARN_ON_ONCE(!chip)) + return -ENODEV; + + if (chip->irq_set_irqchip_state) + break; + + data = irqd_get_parent_data(data); + } while (data); + + if (data) + return chip->irq_set_irqchip_state(data, which, val); + return -EINVAL; +} + /** * irq_set_irqchip_state - set the state of a forwarded interrupt. * @irq: Interrupt line that is forwarded to a VM @@ -2749,25 +2771,8 @@ EXPORT_SYMBOL_GPL(irq_get_irqchip_state); */ int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which, bool val) { - scoped_irqdesc_get_and_buslock(irq, 0) { - struct irq_data *data = irq_desc_get_irq_data(scoped_irqdesc); - struct irq_chip *chip; - - do { - chip = irq_data_get_irq_chip(data); - - if (WARN_ON_ONCE(!chip)) - return -ENODEV; - - if (chip->irq_set_irqchip_state) - break; - - data = irqd_get_parent_data(data); - } while (data); - - if (data) - return chip->irq_set_irqchip_state(data, which, val); - } + scoped_irqdesc_get_and_buslock(irq, 0) + return __irq_set_irqchip_state(scoped_irqdesc, which, val); return -EINVAL; } EXPORT_SYMBOL_GPL(irq_set_irqchip_state); -- 2.53.0