From: Oleg Nesterov <oleg@redhat.com>
To: David Laight <david.laight.linux@gmail.com>
Cc: Xia Fukun <xiafukun@huawei.com>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@kernel.org>,
"Li,Rongqing" <lirongqing@baidu.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"vschneid@redhat.com" <vschneid@redhat.com>,
"mgorman@suse.de" <mgorman@suse.de>,
"bsegall@google.com" <bsegall@google.com>,
"rostedt@goodmis.org" <rostedt@goodmis.org>,
"dietmar.eggemann@arm.com" <dietmar.eggemann@arm.com>,
"vincent.guittot@linaro.org" <vincent.guittot@linaro.org>,
"juri.lelli@redhat.com" <juri.lelli@redhat.com>,
"Zhangqiao (2012 lab)" <zhangqiao22@huawei.com>
Subject: Re: [????] Re: divide error in x86 and cputime
Date: Sun, 4 Jan 2026 21:30:39 +0100 [thread overview]
Message-ID: <aVrN7zNyo3v-y_m3@redhat.com> (raw)
In-Reply-To: <20260104181501.740884d5@pumpkin>
On 01/04, David Laight wrote:
>
> On Sun, 4 Jan 2026 15:23:19 +0100
> Oleg Nesterov <oleg@redhat.com> wrote:
>
> > Peter, Ingo,
> >
> > can you take
> >
> > [PATCH v3 0/2] x86/math64: handle #DE in mul_u64_u64_div_u64()
> > https://lore.kernel.org/all/20250815164009.GA11676@redhat.com/
> >
> > ? at least 1/2 which fixes the problem with #DE ...
>
...
> But this code needs a completely different fix.
Of course, this is clear. The fix above doesn't even try to address the
problems in cputime_adjust() paths.
But. To me the fix above makes sense regardless. mul_u64_u64_div_u64()
should nevet trigger #DE, and I thought that we already discussed this
before.
Do you agree?
Oleg.
next prev parent reply other threads:[~2026-01-04 20:30 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-07 8:14 divide error in x86 and cputime Li,Rongqing
2025-07-07 15:11 ` Steven Rostedt
2025-07-07 22:09 ` Oleg Nesterov
2025-07-07 22:20 ` Steven Rostedt
2025-07-07 22:33 ` Steven Rostedt
2025-07-07 23:00 ` Oleg Nesterov
2025-07-08 11:00 ` David Laight
2025-07-08 1:40 ` 答复: [????] " Li,Rongqing
2025-07-08 1:53 ` Steven Rostedt
2025-07-08 1:58 ` 答复: [????] " Li,Rongqing
2025-07-08 2:05 ` Steven Rostedt
2025-07-08 2:17 ` Oleg Nesterov
2025-07-08 9:58 ` David Laight
2025-07-07 22:30 ` Oleg Nesterov
2025-07-07 23:41 ` 答复: [????] " Li,Rongqing
2025-07-07 23:53 ` Steven Rostedt
2025-07-08 0:10 ` 答复: [????] " Li,Rongqing
2025-07-08 0:30 ` Steven Rostedt
2025-07-08 1:17 ` 答复: [????] " Li,Rongqing
2025-07-08 1:41 ` Steven Rostedt
2025-07-08 10:35 ` [????] Re: [????] " David Laight
2025-07-08 11:12 ` 答复: [????] " Li,Rongqing
2025-07-08 0:23 ` 答复: " Li,Rongqing
2026-01-04 13:23 ` Xia Fukun
2026-01-04 14:23 ` Oleg Nesterov
2026-01-04 18:15 ` David Laight
2026-01-04 20:30 ` Oleg Nesterov [this message]
2026-01-04 22:03 ` David Laight
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