From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f197.google.com (mail-oi1-f197.google.com [209.85.167.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4CD3848BD56 for ; Fri, 4 Sep 2026 17:31:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.197 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788543117; cv=none; b=UtiWw4rmyyx3HL06FR3ibKw2MG4q13xobwBUGBFCZ55w8/4XhgXwbtJ29jFOKXyPRIZOm7IphrzZdOAnEooa/njZ/cIMMTphPw0VkAIwDzoKkHvQrMvvYofKhHl8cvQYIA9zkGiIuhsUNxgbnskCvoVveGZ33wspPFViEUVUy64= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788543117; c=relaxed/simple; bh=CwxNiV+6cxQL0zBKZQS8TnMWY5wyqs+1hcKMKWmAWPM=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=CXe3GWYLHIQzwfV+ys/595fWvwOBskperYkrecB7m1GffqVuNxzwcgRtE/f5rM722aSBneqW/RzOumuNBaEgJlokQ0cZKYBHwqpLd5WhW5yz41QS5IcgEaYWthk0YMqM2SV6/wjORBThY/CMy2w6qKr7bhsfS1NENMrr08hd/Bk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--stevensd.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=ARNGHKPx; arc=none smtp.client-ip=209.85.167.197 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--stevensd.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ARNGHKPx" Received: by mail-oi1-f197.google.com with SMTP id 5614622812f47-4ab8b4887d4so1012420b6e.1 for ; Fri, 04 Sep 2026 10:31:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1788543115; x=1789147915; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:mime-version:date:from :to:cc:subject:date:message-id:reply-to:content-type; bh=6tqulB8FDTNVxXNeXDPTSBTeFrFMPJvixAJvKQn0AlQ=; b=ARNGHKPxNENuTFhziYMvSucNOztmhDbkGo1SC9zAAoxP56hlUe+tP7xZqWnJeCLW05 k9srbsIJYSImX1uzzB5bI4nZicRbrVQP4M0oBxVmoAk+MLWnCfQzTc9JUKdMyH8teN+c IhzDxplnz3+8F31OpVI5RhnzLAcqLGHVPGWC1vZ2E/x8bC70pKnwHvg44ttAs3zTjTFW +/5ukKwvT6Mo7huGkMNR058RPCW4J/zuGrS+G/iL1Oh5/rVc+wrcT7H6Ebk19TH0ToZo dp0ZthIgbdgSJlBAy2n4w+CH6Y/2F64lL1kepNho0PMejJ/47FIo+NZGTgbgZ3FDf+hZ SuPw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788543115; x=1789147915; h=content-type:cc:to:from:subject:message-id:mime-version:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=6tqulB8FDTNVxXNeXDPTSBTeFrFMPJvixAJvKQn0AlQ=; b=a1mlrdolZaMMmqkFUp5yTdrIfh4bqw8DLTMvu9lLfsXBi6vj/Sx9U3sXGjw41qr4WE cEfVKuUsowgmM5lNaDkmSuldPqN56WeZGhTh0Jyw6kECFxGDzwvsgUfSAiwDS3yO/Om3 4utVSHgyUmR9SmGbIZo9/wzrBHlT4Cv85LGiUQVlQpf4jb1/PPf1PmBk406QNyeVn36D BATaJ4f0iu1ZBSEX+KN0awU3EOCzaaI8zLCgTB1DiCwAt3KouoyERRSu/wo8pvrKJk0D bz0BSyMhp9oBBD4GzFMgQFEZGfW4uvXciqF9cHqGcWUJ5GO1+jcBjBcTG2gRbrYmAYfX 2neQ== X-Forwarded-Encrypted: i=1; AKwUvBxmzyfU2fnWLVDSj+At0t82xYtp/cbXPO2y7pYy2grek9rfdAgD7+M34zhZR9k6k9L+qpDCXqyxIFUGEkU=@vger.kernel.org X-Gm-Message-State: AFuF++m7Xv0NFO/Y5p3bWsjQadaSyilcXkGwW79MdXnMWslNorOry3i6 C4XspGRoJNOPZ+26jfrpVube5Qv/6Ah2GUVcxZid6QPcg4xcBLMk3atLQ+8TQBrqz9XogKz8pGk D9Q5QvKKxRt9WkA== X-Received: from dyjh19.prod.google.com ([2002:a05:7300:5613:b0:315:877c:f169]) (user=stevensd job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6820:60b:b0:6b7:8396:f3c2 with SMTP id 006d021491bc7-6b78396f7ecmr3028618eaf.36.1788543114426; Fri, 04 Sep 2026 10:31:54 -0700 (PDT) Date: Fri, 4 Sep 2026 10:31:45 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.55.0.979.g7e5102b832-goog Message-ID: <20260904173145.2028377-1-stevensd@google.com> Subject: [PATCH v2] memcg: Don't call schedule_work when no spinning is allowed From: David Stevens To: Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , Andrew Morton Cc: Lorenzo Stoakes , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, David Stevens , Michal Hocko Content-Type: text/plain; charset="UTF-8" Memcg charging can be done from any context, but calling schedule_work() isn't safe from an NMI. If memory.high is breached from a context where spinning isn't allowed, use irq_work to schedule the reclaim work. Fixes: 3ac4638a734a ("memcg: make memcg_rstat_updated nmi safe") Acked-by: Michal Hocko Signed-off-by: David Stevens --- v2: - Added missing includes reported by Lorenzo and kernel test robot - Added Acked-by include/linux/memcontrol.h | 2 ++ mm/memcontrol.c | 13 ++++++++++++- 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 8170bb8066a2..4a5ef0aba475 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -23,6 +23,7 @@ #include #include #include +#include struct mem_cgroup; struct obj_cgroup; @@ -219,6 +220,7 @@ struct mem_cgroup { spinlock_t peaks_lock; /* Range enforcement for interrupt charges */ + struct irq_work high_irq_work; struct work_struct high_work; #ifdef CONFIG_ZSWAP diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 6dc4888a90f3..0e8b302ca9ad 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -62,6 +62,7 @@ #include #include #include +#include #include "internal.h" #include "swap_table.h" #include @@ -2360,6 +2361,11 @@ static void high_work_func(struct work_struct *work) reclaim_high(memcg, MEMCG_CHARGE_BATCH, GFP_KERNEL); } +static void high_irq_work_func(struct irq_work *work) +{ + schedule_work(&container_of(work, struct mem_cgroup, high_irq_work)->high_work); +} + /* * Clamp the maximum sleep time per allocation batch to 2 seconds. This is * enough to still cause a significant slowdown in most cases, while still @@ -2752,7 +2758,10 @@ static int try_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp_mask, /* Don't bother a random interrupted task */ if (!in_task()) { if (mem_high) { - schedule_work(&memcg->high_work); + if (allow_spinning) + schedule_work(&memcg->high_work); + else + irq_work_queue(&memcg->high_irq_work); break; } continue; @@ -4129,6 +4138,7 @@ static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent) goto fail; INIT_WORK(&memcg->high_work, high_work_func); + init_irq_work(&memcg->high_irq_work, high_irq_work_func); vmpressure_init(&memcg->vmpressure); INIT_LIST_HEAD(&memcg->memory_peaks); INIT_LIST_HEAD(&memcg->swap_peaks); @@ -4337,6 +4347,7 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css) static_branch_dec(&memcg_bpf_enabled_key); vmpressure_cleanup(&memcg->vmpressure); + irq_work_sync(&memcg->high_irq_work); cancel_work_sync(&memcg->high_work); memcg1_remove_from_trees(memcg); free_shrinker_info(memcg); base-commit: 8d3ae59288f1e7d58d76558a6ee96d533bc5019f -- 2.55.0.979.g7e5102b832-goog