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 AA0AD528428; Tue, 29 Sep 2026 17:38:21 +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=1790703502; cv=none; b=SArsEbVuPOF0gAI2ne5S4GyfBLDt4WK0UKkD5kuiDx7SGNsoJIn4GgSWJuX144EBCkC5IophOU6V73Bs7qpB5y6baH23CPVF/7FyuvNjKAteL/boaBXsTwDQxiLB7aPDjzcHIPU29l/lucI40ycEbcr6ZjgOAYsdQYn8RZj0z5Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790703502; c=relaxed/simple; bh=sMhfOsYRlw1oNQeIkAXv0p6U0oqD1y16erHz8e1YB3Y=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=qakJUzx/SoWBl/gRXLBVefltaERxJNJWzJqKy1ecknXrHtNCa17czgxwXPJwNOrGbbD3dhWt0Tq7HPW1a415lGbO3Zqbdhg/7rzXzuT+CCsw7PLi/rrvzB6iHfNkh1klNNwOrzqyiQnNMQ5zsEANkMVkzaUXeUD1+wqAXn4rfeM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GZbgz6Kg; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="GZbgz6Kg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 125081F000FF; Tue, 29 Sep 2026 17:38:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790703501; bh=gHHVxQFAvN3ZcewoO3CLmw+cArQRBdv7a5OEkmGubew=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=GZbgz6Kg3g0TGR1XlshPjv6nsnkmWt2zQzGKU4s2lzMf7he6YaUmt/e3WAwGTL4wK Wc3O+hZgiWeK60t9msqX56eOWvQmrSOFznEvDI93eml3VdH5Twea7WRfyQtVd2fYht xDAedgMy9tIHH9WcQw9Ye+jXmrPB5tYfz/b8LEHZ+uNlGuSTqkScL1D88q4JJlJUZ+ fDq7TliPyjEDbusyhRoVLK4+YvOsmOa4FBN2bjadXwM44OJ5mRzjKOdGkfRSpjTUn5 qBF03zxBwNC4tn6qGRkqw347/bPck/w8q01xOZBT2FPcxjUFzdHAFBeBeoxlkAaHBQ V32OtGLvH3OqQ== From: sashiko-bot@kernel.org Subject: Re: [PATCH sched_ext/for-7.4] sched_ext: Work around pahole 1.32 dropping scx_bpf_task_set_lazy_resched() from BTF Reply-To: sashiko-reviews@lists.linux.dev To: "Tejun Heo" Cc: bpf@vger.kernel.org, sched-ext@lists.linux.dev In-Reply-To: <7c139810be5ffc9764ed4236efc28794@kernel.org> References: <7c139810be5ffc9764ed4236efc28794@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 29 Sep 2026 17:38:20 +0000 Message-Id: <20260929173821.125081F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: sched-ext@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Thank you for your contribution! Sashiko AI review found 1 potential issue(= s) to consider: - [Low] sched: build failure due to misapplied patch in scx_bpf_task_set_ds= q_vtime() -- commit 16f6b2129331609ed5db39cd3ea7260f54a1df1f Author: Tejun Heo sched_ext: Work around pahole 1.32 dropping scx_bpf_task_set_lazy_resched()= from BTF This commit works around an issue with pahole 1.32 by forcing the lazy argument onto the stack using barrier_data() so its location doesn't name a register. Link: https://lore.kernel.org/r/20260925213619.2187751-1-yonghong.song@linu= x.dev > diff --git a/kernel/sched/ext/ext.c b/kernel/sched/ext/ext.c > index 6b037d27c99d3..feaa784d7a0dc 100644 > --- a/kernel/sched/ext/ext.c > +++ b/kernel/sched/ext/ext.c > @@ -10119,6 +10119,11 @@ __bpf_kfunc bool scx_bpf_task_set_dsq_vtime(stru= ct task_struct *p, u64 vtime, > { > struct scx_sched *sch; > =20 > + /* > + * clang's register locations for @lazy make pahole 1.32 drop this kfunc > + * from BTF. Keep @lazy in memory so its location names no register. > + */ > + barrier_data(&lazy); [Severity: Low] Will this cause a build failure? It looks like the lazy variable is not declared in scx_bpf_task_set_dsq_vtime(). Could it be that this patch was mistakenly applied to=20 scx_bpf_task_set_dsq_vtime() instead of scx_bpf_task_set_lazy_resched()?=20 They appear to share identical context lines, meaning the patch might have matched guard(rcu)(); followed by sch =3D scx_prog_sched(aux); in the wrong function. > guard(rcu)(); > sch =3D scx_prog_sched(aux); > if (unlikely(!sch || !scx_task_on_sched(sch, p))) > return false; --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/7c139810be5ffc9764e= d4236efc28794@kernel.org?part=3D1