From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 91706439336; Tue, 21 Jul 2026 21:08:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784668109; cv=none; b=e19yVslieA5o0cRfEJSG1XbLVVyS/m8A/H4/hdsxxZjwsiyzUzpilEkd1bzZW0dE+W1PR6D8nr3s4j/ryUovadn5D890QDu+ecq1gNzOUroGmo4eskzZXTX2NqYvTwJFDqXKPiDn5Qc2I/xx4WUDJxbdWqSYdp3Jrv7eBqXFVEA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784668109; c=relaxed/simple; bh=0wjGgFlS1qQWq3ZJkj/cl7TGrAueKVnT+8mtowyss/o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Qb8OcMp7pxG+SQ+i+XAF2ecEBjOo4vbUlwhLcNu+FMNNRmXTpsDvSTF4gf4wP29SmwhSl+H+beK+2rXRZoyUqytbTNIGm9Hf/rCFG7PfKpiVZtTZvCuxEnfwcT2t3511vZq1vodNn6uXN/bpi6KBhXs07K6a04lQ3TQe7igVE6I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=iajxXFs4; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="iajxXFs4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A66C71F000E9; Tue, 21 Jul 2026 21:08:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784668108; bh=d/uJJnTq8GFA0bx5fXbCNn+SIpMMh2fiX80JgIQyxXo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=iajxXFs4ZQNPKxvszQzujPWeCUOIHmS+fRO1u0XPPJBGhLNVXGuMW6gKoZO9sssJo Nvo6nltvPhgTVM7NEUpelnHzeHgJ6XAL2a7VLHqkcocSJvhTfSolaprpB0T/9Z9m9r PqcVH+aCcIOqrBRcL5T+Hkk/mVQR2wY7537DErN4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Taeyang Lee <0wn@theori.io>, "Peter Zijlstra (Intel)" , Sasha Levin Subject: [PATCH 6.1 0049/1067] perf/core: Detach event groups during remove_on_exec Date: Tue, 21 Jul 2026 17:10:50 +0200 Message-ID: <20260721152425.661072905@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152424.521567757@linuxfoundation.org> References: <20260721152424.521567757@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Taeyang Lee <0wn@theori.io> [ Upstream commit 037a3c43edfb597665dd34457cd22b14692f2ba3 ] perf_event_remove_on_exec() removes events by calling perf_event_exit_event(). For top-level events, this removes the event from the context with DETACH_EXIT only. This can leave inconsistent group state when a removed event is a group leader and the group contains siblings without remove_on_exec. If the group was active, the surviving siblings can remain active and attached to the removed leader's sibling list, but are no longer represented by a valid group leader on the PMU context active lists. A later close of the removed leader uses DETACH_GROUP and can promote the still-active siblings from this stale group state. The next schedule-in can then add an already-linked active_list entry again, corrupting the PMU context active list. With DEBUG_LIST enabled, this is caught as a list_add double-add in merge_sched_in(). Fix this by detaching group relationships when remove_on_exec removes an event. This preserves the existing task-exit and revoke behavior, while ensuring surviving siblings are ungrouped before the removed event leaves the context. Fixes: 2e498d0a74e5 ("perf: Add support for event removal on exec") Signed-off-by: Taeyang Lee <0wn@theori.io> Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/ai65GgZcC0LAlWLG@Taeyangs-MacBook-Pro.local Signed-off-by: Sasha Levin --- kernel/events/core.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 146b37e97832a9..1478bad56e40a1 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4334,7 +4334,8 @@ static void perf_event_enable_on_exec(int ctxn) static void perf_remove_from_owner(struct perf_event *event); static void perf_event_exit_event(struct perf_event *event, - struct perf_event_context *ctx); + struct perf_event_context *ctx, + unsigned long detach_flags); /* * Removes all events from the current task that have been marked @@ -4365,7 +4366,7 @@ static void perf_event_remove_on_exec(int ctxn) modified = true; - perf_event_exit_event(event, ctx); + perf_event_exit_event(event, ctx, DETACH_GROUP); } raw_spin_lock_irqsave(&ctx->lock, flags); @@ -13055,10 +13056,11 @@ static void sync_child_event(struct perf_event *child_event) } static void -perf_event_exit_event(struct perf_event *event, struct perf_event_context *ctx) +perf_event_exit_event(struct perf_event *event, + struct perf_event_context *ctx, + unsigned long detach_flags) { struct perf_event *parent_event = event->parent; - unsigned long detach_flags = 0; if (parent_event) { /* @@ -13073,7 +13075,7 @@ perf_event_exit_event(struct perf_event *event, struct perf_event_context *ctx) * Do destroy all inherited groups, we don't care about those * and being thorough is better. */ - detach_flags = DETACH_GROUP | DETACH_CHILD; + detach_flags |= DETACH_GROUP | DETACH_CHILD; mutex_lock(&parent_event->child_mutex); } @@ -13158,7 +13160,7 @@ static void perf_event_exit_task_context(struct task_struct *child, int ctxn) perf_event_task(child, child_ctx, 0); list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) - perf_event_exit_event(child_event, child_ctx); + perf_event_exit_event(child_event, child_ctx, 0); mutex_unlock(&child_ctx->mutex); -- 2.53.0