From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from esa3.hc555-34.eu.iphmx.com (esa3.hc555-34.eu.iphmx.com [207.54.77.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DAA2F2AD03 for ; Mon, 12 Oct 2026 09:14:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=207.54.77.50 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791796457; cv=none; b=faHjobXtG1D8jHT46N711LaU6pGVQWwmpnmeJW+BEICz6OYQICPLQezK83zJyzKtYma+BnD5GkDDcfT9XLCYAXWdJtnt+IHsHs8kxMksamczDmK8HQ8w9ulg2fqLV09qrD1RaO/5v1O7sLoah8Ws6DUG7PurMwo53YfyrY+hd6g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791796457; c=relaxed/simple; bh=RUboTfQiUPP76+VWIJzfRXec6oAYPgqZ2bmu4E3lnGs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=FEMd0gLoHLLUZkLGb4LXEC5SKllIg0v6MBejOCOzoHilFjsPwIea4SLMW5HWAQqqn22F6TGdRL+0z4bnI31JzZTDoDMNj/GDGVlv4XzU7GHtfrVZDCNCJdT/dWAmzeg9lJodCANEc5Ajbj9ycDaJ9So9LuLInUfc2BFKsLRDETI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=mobileye.com; spf=pass smtp.mailfrom=mobileye.com; dkim=fail (0-bit key) header.d=mobileye.com header.i=@mobileye.com header.b=paQgpkrZ reason="key not found in DNS"; arc=none smtp.client-ip=207.54.77.50 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=mobileye.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mobileye.com Authentication-Results: smtp.subspace.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=mobileye.com header.i=@mobileye.com header.b="paQgpkrZ" DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=mobileye.com; i=@mobileye.com; q=dns/txt; s=MoEyIP; t=1791796455; x=1823332455; h=from:date:subject:mime-version:content-transfer-encoding: message-id:to:cc; bh=RUboTfQiUPP76+VWIJzfRXec6oAYPgqZ2bmu4E3lnGs=; b=paQgpkrZURLn04CtGp1kbKuSgii1wqswrxTDkE0riM6bTZ01Tu9xZl9X gsi14LBIKVZ5IVluGwtaRMev0/hBTtNTdKMsWSxirRe9Nk2hwyz6Sl59X DzXFXNbC7whXSMOZvJoLM0mYSGOQW55Dbx5wRVXAdJ6ImLrMfL879ncvM W5h4a0XscWPoXEdWGIDV3TtAhh4wRcu705w5zqm3WPr+7ukAWlnrabpm4 5D1GDFC6Yvy+6Cj8LrDoT2043lg/W+uv4UinGzpMTe6F07sIGYt7JOJ5b 0rtHBM7GqTufcCTL8k0gIjWY0bRkVXQHmKYhXF++1LYn0hdWXsZPxcHmv Q==; X-CSE-ConnectionGUID: DZomWcbJQrKnf7LEiIjYkQ== X-CSE-MsgGUID: cQGSfrF7QZi3g6C0e+ERHA== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from unknown (HELO ces01_data.me-corp.lan) ([146.255.191.134]) by esa3.hc555-34.eu.iphmx.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Oct 2026 12:13:03 +0300 X-CSE-ConnectionGUID: rEWvfetiQ1iP5W/OjNINWg== X-CSE-MsgGUID: BJlt/lpRT8WsWVNxy4Kuvg== Received: from unknown (HELO epgd071.me-corp.lan) ([10.154.54.3]) by ces01_data.me-corp.lan with SMTP; 12 Oct 2026 12:20:35 +0300 Received: by epgd071.me-corp.lan (sSMTP sendmail emulation); Mon, 12 Oct 2026 12:13:01 +0300 From: Vladimir Kondratiev Date: Mon, 12 Oct 2026 12:12:59 +0300 Subject: [PATCH v3] irqchip/riscv-aplic: fix asynchronous probing Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261012-aplic-async-probe-v3-1-5cf52dc28690@mobileye.com> X-B4-Tracking: v=1; b=H4sIAJqkzGoC/4XNQQ6DIBCF4asY1qUBRERXvUfThY5jnUTFQENqj HcvuuyiXf4vmW82FtATBlZnG/MYKZCbU+SXjMHQzE/k1KVmSigjhVS8WUYC3oR1Br541yK30ii NIi+MKFm6Wzz29D7N+yP1QOHl/Hq+iPJYf2lRcsk1KNB90YpKmtvkWhpxxSu4iR1gVH8RlRBrb Fcaq6HqvpF93z+5t1n0+gAAAA== X-Change-ID: 20261012-aplic-async-probe-81624e035607 To: Anup Patel , Thomas Gleixner , Radu Rendec , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Sebastian Andrzej Siewior , Clark Williams , Steven Rostedt , Jessica Liu Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, Vladimir Kondratiev X-Mailer: b4 0.14.2 boolean flag don't protect from race when probing several instances asynchronously. On system with multiple APLICs, if probed asynchronously, warning triggered as below. [ 0.227210] riscv-aplic 67560000.interrupt-controller: 257 interrupts directly connected to 8 CPUs [ 0.227210] riscv-aplic 674e0000.interrupt-controller: 257 interrupts directly connected to 8 CPUs [ 0.227224] ------------[ cut here ]------------ [ 0.227227] list_add double add: new=ffffffff8130ced0, prev=ffffffff8130ced0, next=ffffffff81316d40. [ 0.227302] WARNING: lib/list_debug.c:35 at __list_add_valid_or_report+0xe0/0xe6, CPU#4: kworker/u97:0/211 [ 0.227322] Modules linked in: [ 0.227333] CPU: 4 UID: 0 PID: 211 Comm: kworker/u97:0 Not tainted 7.3.0-rc6 #1 PREEMPT_RT [ 0.227341] Hardware name: EyeQ7H evaluation board (DT) [ 0.227346] Workqueue: async async_run_entry_fn [ 0.227358] epc : __list_add_valid_or_report+0xe0/0xe6 [ 0.227366] ra : __list_add_valid_or_report+0xe0/0xe6 [ 0.227375] epc : ffffffff804a08a0 ra : ffffffff804a08a0 sp : ffffffc600823b90 [ 0.227379] gp : ffffffff81389e70 tp : ffffffd60135ee00 t0 : 0000000000000000 [ 0.227383] t1 : 3fffffffffffffff t2 : 0000000000000000 s0 : ffffffc600823bb0 [ 0.227387] s1 : ffffffff8130ced0 a0 : 0000000000000058 a1 : ffffffd9efc9e5c0 [ 0.227391] a2 : ffffffd9efd5c510 a3 : 0000000000000000 a4 : 0000000000000000 [ 0.227395] a5 : 0000000000000000 a6 : ffffffd9efc6e5c0 a7 : bfffffffffffe000 [ 0.227399] s2 : 0000000000000000 s3 : ffffffff8130ce28 s4 : 0000000000000000 [ 0.227402] s5 : ffffffd6018b65c8 s6 : 0000000000000000 s7 : ffffffd6012fd605 [ 0.227406] s8 : ffffffd6010c3400 s9 : 0000000000000000 s10: 0000000000000000 [ 0.227409] s11: 0000000000000000 t3 : 3fffffffffffe000 t4 : 0000000000000020 [ 0.227413] t5 : 0000000000000000 t6 : ffffffc6008238f8 ssp : 0000000000000000 [ 0.227417] status: 0000000200000120 badaddr: ffffffff804a08a0 cause: 0000000000000003 [ 0.227422] [] __list_add_valid_or_report+0xe0/0xe6 [ 0.227432] [] register_syscore+0x30/0x60 [ 0.227444] [] aplic_probe+0xd2/0xfa [ 0.227453] [] platform_probe+0x3e/0x7a [ 0.227461] [] really_probe+0x88/0x35c [ 0.227469] [] __driver_probe_device+0xc0/0x13a [ 0.227478] [] driver_probe_device+0x38/0xb2 [ 0.227486] [] __driver_attach_async_helper+0x3c/0xc4 [ 0.227493] [] async_run_entry_fn+0x28/0x154 [ 0.227500] [] process_one_work+0x14e/0x3d2 [ 0.227509] [] worker_thread+0x144/0x286 [ 0.227516] [] kthread+0xee/0x10e [ 0.227524] [] ret_from_fork_kernel+0x18/0x14e [ 0.227532] [] ret_from_fork_kernel_asm+0x16/0x18 [ 0.227542] ---[ end trace 0000000000000000 ]--- [ 0.228475] pinctrl-single 48508000.pinctrl: 512 pins, size 2048 [ 0.228500] pinctrl-single 53838000.pinctrl: 512 pins, size 2048 [ 0.228723] pinctrl-single 67107000.pinctrl: 512 pins, size 2048 [ 0.227210] riscv-aplic 674e0000.interrupt-controller: 257 interrupts directly connected to 8 CPUs [ 0.227224] ------------[ cut here ]------------ [ 0.227227] list_add double add: new=ffffffff8130ced0, prev=ffffffff8130ced0, next=ffffffff81316d40. [ 0.227302] WARNING: lib/list_debug.c:35 at __list_add_valid_or_report+0xe0/0xe6, CPU#4: kworker/u97:0/211 [ 0.227322] Modules linked in: [ 0.227333] CPU: 4 UID: 0 PID: 211 Comm: kworker/u97:0 Not tainted 7.3.0-rc6 #1 PREEMPT_RT [ 0.227341] Hardware name: EyeQ7H evaluation board (DT) [ 0.227346] Workqueue: async async_run_entry_fn [ 0.227358] epc : __list_add_valid_or_report+0xe0/0xe6 [ 0.227366] ra : __list_add_valid_or_report+0xe0/0xe6 [ 0.227375] epc : ffffffff804a08a0 ra : ffffffff804a08a0 sp : ffffffc600823b90 [ 0.227379] gp : ffffffff81389e70 tp : ffffffd60135ee00 t0 : 0000000000000000 [ 0.227383] t1 : 3fffffffffffffff t2 : 0000000000000000 s0 : ffffffc600823bb0 [ 0.227387] s1 : ffffffff8130ced0 a0 : 0000000000000058 a1 : ffffffd9efc9e5c0 [ 0.227391] a2 : ffffffd9efd5c510 a3 : 0000000000000000 a4 : 0000000000000000 [ 0.227395] a5 : 0000000000000000 a6 : ffffffd9efc6e5c0 a7 : bfffffffffffe000 [ 0.227399] s2 : 0000000000000000 s3 : ffffffff8130ce28 s4 : 0000000000000000 [ 0.227402] s5 : ffffffd6018b65c8 s6 : 0000000000000000 s7 : ffffffd6012fd605 [ 0.227406] s8 : ffffffd6010c3400 s9 : 0000000000000000 s10: 0000000000000000 [ 0.227409] s11: 0000000000000000 t3 : 3fffffffffffe000 t4 : 0000000000000020 [ 0.227413] t5 : 0000000000000000 t6 : ffffffc6008238f8 ssp : 0000000000000000 [ 0.227417] status: 0000000200000120 badaddr: ffffffff804a08a0 cause: 0000000000000003 [ 0.227422] [] __list_add_valid_or_report+0xe0/0xe6 [ 0.227432] [] register_syscore+0x30/0x60 [ 0.227444] [] aplic_probe+0xd2/0xfa [ 0.227453] [] platform_probe+0x3e/0x7a [ 0.227461] [] really_probe+0x88/0x35c [ 0.227469] [] __driver_probe_device+0xc0/0x13a [ 0.227478] [] driver_probe_device+0x38/0xb2 [ 0.227486] [] __driver_attach_async_helper+0x3c/0xc4 [ 0.227493] [] async_run_entry_fn+0x28/0x154 [ 0.227500] [] process_one_work+0x14e/0x3d2 [ 0.227509] [] worker_thread+0x144/0x286 [ 0.227516] [] kthread+0xee/0x10e [ 0.227524] [] ret_from_fork_kernel+0x18/0x14e [ 0.227532] [] ret_from_fork_kernel_asm+0x16/0x18 [ 0.227542] ---[ end trace 0000000000000000 ]--- Fixes: b330fbfd34d7 ("irqchip/riscv-aplic: Register syscore operations only once") Signed-off-by: Vladimir Kondratiev --- Changes in v3: - drop __ro_after_init attribute due to write to read-only page concern - Link to v2: https://lore.kernel.org/r/20261012-aplic-async-probe-v2-1-868d7684c9d6@mobileye.com Changes in v2: - fixed potential access to read-only page - Link to v1: https://lore.kernel.org/r/20261012-aplic-async-probe-v1-1-4c2c4f5b0916@mobileye.com --- drivers/irqchip/irq-riscv-aplic-main.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/irqchip/irq-riscv-aplic-main.c b/drivers/irqchip/irq-riscv-aplic-main.c index d9afb6ae98cf56d6fd9f858c31a3d23546c3b450..54e1d5602f15a04127e900c0a4983022d49da553 100644 --- a/drivers/irqchip/irq-riscv-aplic-main.c +++ b/drivers/irqchip/irq-riscv-aplic-main.c @@ -116,14 +116,12 @@ static struct syscore aplic_syscore = { .ops = &aplic_syscore_ops, }; -static bool aplic_syscore_registered __ro_after_init; +static atomic_t aplic_syscore_registered = ATOMIC_INIT(0); static void aplic_syscore_init(void) { - if (!aplic_syscore_registered) { + if (!atomic_cmpxchg(&aplic_syscore_registered, 0, 1)) register_syscore(&aplic_syscore); - aplic_syscore_registered = true; - } } static int aplic_pm_notifier(struct notifier_block *nb, unsigned long action, void *data) --- base-commit: 24a19b953e2a3d0ea5a8c4951a0ab8f32720c907 change-id: 20261012-aplic-async-probe-81624e035607 Best regards, -- Vladimir Kondratiev