From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga05-in.huawei.com (szxga05-in.huawei.com [45.249.212.191]) (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 0588A2E093A for ; Thu, 21 Aug 2025 06:53:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.191 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755759190; cv=none; b=QVXOSpvv9Z6iWisasINpjXHt1HOEahQFanOnH6iCyutS4EqR1CCyR5q7tkKRJ5ruieTI5qo+uXFSrJqeLBOMVo7My1Yize0PDRaBdQ6aHimNhTSi9N4twym1FNCIziw0OnSTv9RMU1+4kueiG+hINNd/8tdhCx4L4cAx09xKceU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755759190; c=relaxed/simple; bh=RmmERoEA013CqYqHZ/gUF7ZZnNFcE/eoBYkAwXxdRCo=; h=Subject:To:CC:References:From:Message-ID:Date:MIME-Version: In-Reply-To:Content-Type; b=tZtbXhwbON0wkrf0d34FpBjt2maTGsiTxdhm6NWlHs7bN1gCt2WWOj4cIzm7/ehRk27THmQFEWM2EdQasWjVku1M4KJOocutwObq5azJxe7ua9pZWx3+L9WaA1qafC2BamIFLE18ZAtV/UX0LNr53dTZwPXrF6U+IvTkn112LAg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.191 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.162.112]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4c6v8K6Wbdz2gLPM; Thu, 21 Aug 2025 14:50:09 +0800 (CST) Received: from kwepemk200017.china.huawei.com (unknown [7.202.194.83]) by mail.maildlp.com (Postfix) with ESMTPS id 6859A1400DA; Thu, 21 Aug 2025 14:53:03 +0800 (CST) Received: from [10.174.178.219] (10.174.178.219) by kwepemk200017.china.huawei.com (7.202.194.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Thu, 21 Aug 2025 14:53:02 +0800 Subject: Re: [PATCH] irqchip/gic-v5: Fix kmemleak L2 IST table entries false positives To: Lorenzo Pieralisi CC: , , Jinjie Ruan , Thomas Gleixner , Marc Zyngier References: <20250811135001.1333684-1-lpieralisi@kernel.org> From: Zenghui Yu Message-ID: <82bac373-21d6-7aab-0b3d-509b5bce25db@huawei.com> Date: Thu, 21 Aug 2025 14:53:02 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <20250811135001.1333684-1-lpieralisi@kernel.org> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-ClientProxiedBy: kwepems200001.china.huawei.com (7.221.188.67) To kwepemk200017.china.huawei.com (7.202.194.83) On 2025/8/11 21:50, Lorenzo Pieralisi wrote: > L2 IST table entries are allocated with the kmalloc interface > and their physical addresses are programmed in the GIC (either > IST base address register or L1 IST table entries) but their > virtual addresses are not stored in any kernel data structure > because they are not needed at runtime - the L2 IST table entries > are managed through system instructions but never dereferenced > directly by the driver. > > This triggers kmemleak false positive reports: > > unreferenced object 0xffff00080039a000 (size 4096): > comm "swapper/0", pid 0, jiffies 4294892296 > hex dump (first 32 bytes): > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace (crc 0): > kmemleak_alloc+0x34/0x40 > __kmalloc_noprof+0x320/0x464 > gicv5_irs_iste_alloc+0x1a4/0x484 > gicv5_irq_lpi_domain_alloc+0xe4/0x194 > irq_domain_alloc_irqs_parent+0x78/0xd8 > gicv5_irq_ipi_domain_alloc+0x180/0x238 > irq_domain_alloc_irqs_locked+0x238/0x7d4 > __irq_domain_alloc_irqs+0x88/0x114 > gicv5_of_init+0x284/0x37c > of_irq_init+0x3b8/0xb18 > irqchip_init+0x18/0x40 > init_IRQ+0x104/0x164 > start_kernel+0x1a4/0x3d4 > __primary_switched+0x8c/0x94 > > Instruct kmemleak to ignore L2 IST table memory allocation > virtual addresses to prevent these false positive reports. > > Reported-by: Jinjie Ruan > Closes: https://lore.kernel.org/lkml/cc611dda-d1e4-4793-9bb2-0eaa47277584@huawei.com/ > Signed-off-by: Lorenzo Pieralisi > Cc: Thomas Gleixner > Cc: Marc Zyngier > --- > drivers/irqchip/irq-gic-v5-irs.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/irqchip/irq-gic-v5-irs.c b/drivers/irqchip/irq-gic-v5-irs.c > index ad1435a858a4..e8a576f66366 100644 > --- a/drivers/irqchip/irq-gic-v5-irs.c > +++ b/drivers/irqchip/irq-gic-v5-irs.c > @@ -5,6 +5,7 @@ > > #define pr_fmt(fmt) "GICv5 IRS: " fmt > > +#include > #include > #include > #include > @@ -117,6 +118,7 @@ static int __init gicv5_irs_init_ist_linear(struct gicv5_irs_chip_data *irs_data > kfree(ist); > return ret; > } > + kmemleak_ignore(ist); > > return 0; > } > @@ -232,6 +234,7 @@ int gicv5_irs_iste_alloc(const u32 lpi) > kfree(l2ist); > return ret; > } > + kmemleak_ignore(l2ist); Reviewed-by: Zenghui Yu Thanks, Zenghui