From: Peter Zijlstra <peterz@infradead.org>
To: Brian Cain <brian.cain@oss.qualcomm.com>
Cc: linux-kernel@vger.kernel.org, pierrick.bouvier@oss.qualcomm.com,
paulmck@kernel.org, sid.manning@oss.qualcomm.com,
linux-hexagon@vger.kernel.org, "Ingo Molnar" <mingo@kernel.org>,
"Frederic Weisbecker" <frederic@kernel.org>,
"Philippe Mathieu-Daudé" <philmd@oss.qualcomm.com>
Subject: Re: [PATCH v2] smp: align struct __call_single_node to 8 bytes
Date: Thu, 24 Sep 2026 11:34:50 +0200 [thread overview]
Message-ID: <20260924093450.GN2009045@noisy.programming.kicks-ass.net> (raw)
In-Reply-To: <20260923154307.3625611-1-brian.cain@oss.qualcomm.com>
On Wed, Sep 23, 2026 at 08:43:07AM -0700, Brian Cain wrote:
> Consumers walking call_single_queue cast each node to call_single_data_t
> and, given that type's declared over-alignment, the compiler may load
> llist.next and u_flags as one naturally aligned double word. Fields using
> this type, such as task_struct::wake_entry only guarantee pointer alignment,
> which faults on strict-alignment 32-bit architectures like hexagon.
Where exactly does this happen? I'm failing with grep.
next prev parent reply other threads:[~2026-09-24 9:34 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-23 15:43 Brian Cain
2026-09-23 22:09 ` David Laight
2026-09-24 9:34 ` Peter Zijlstra [this message]
2026-09-24 11:04 ` David Laight
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