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charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: EJPoqrKZISjVpA/3s9akh6QOuS0dtqVAqsqCvyaF7HH81tDxEALzsubDrWymsYfA9Mf2o1vnw8pwDGOcI6tsow8WneHMkeo0oUxf/dgyHCEKlmetDH0iNO746DPUBzVSXzTu3j8pS2jcmJkl73fulYYAUEPmUc9z76VTEHRum6vzVPW5dTv2AShWt/M+3c17eU5UiUWMrW1eP3YtmndW8d7oW1J6Tu9zXaDFI7w0Mu4TM7UAxlqMGX5985z10M8jrPq8ATwlz8bs5NWclNCgjqcM0L0QgA2hDtn6u2bLXAFWfvTCGaafLXRRZKK9IXz3GgyrFgy0D0QXQZK6S/08CEZ7Sc5XukfAITcIL6AgJzSw76weVpYEaedfo6v7sajM+YICpCOCepj1JvMoUlrMI2hzJsmz8bSy9HI8q1q/WdAGpH6DNMOg6oNxSPqrW35Q5dQmT06xzQVBLMJ2GDuol7LEWGKAaU62sRmw4PiiXRYBDFMXLIzFeBbxsWaj23Kh9V7+swBCceRvJDGtNVFgkWZCDivJbCnyzs1HIfe4EYF9q/5wjlbDR7QIIXeRsvprBGLWifm18q5EN6ofma4hPWzHxeLGmsAbC9bqYR+PzbHi1mSXHklTEVCbZZJseV7Z X-OriginatorOrg: wdc.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: SN7PR04MB8532.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 42fa786f-a39a-4fee-0669-08de68b46724 X-MS-Exchange-CrossTenant-originalarrivaltime: 10 Feb 2026 14:55:16.6617 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: b61c8803-16f3-4c35-9b17-6f65f441df86 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: 4FkEut/kkFY5nZOHg6uIHE9mWImTE37LGB+vMGKRVU+SzPZnaVvrWHC0bYSDIGgbB9zrWyLoZP3/JZWQ5chK5cJeSLGBROnk7zyxauc2d4s= X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR04MB8855 On Feb 10, 2026 / 14:33, Thomas Gleixner wrote: [...] > Can you please try the fix below? >=20 > Thanks >=20 > tglx > --- > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 854984967fe2..61c2d65156b5 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -10729,10 +10729,9 @@ void sched_mm_cid_exit(struct task_struct *t) > return; > /* > * Mode change. The task has the CID unset > - * already. The CPU CID is still valid and > - * does not have MM_CID_TRANSIT set as the > - * mode change has just taken effect under > - * mm::mm_cid::lock. Drop it. > + * already and dealt with an eventually set > + * TRANSIT bit. If the CID is owned by the CPU > + * then drop it. > */ > mm_drop_cid_on_cpu(mm, this_cpu_ptr(mm->mm_cid.pcpu)); > } > diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h > index bd350e40859d..1b4283e9edc3 100644 > --- a/kernel/sched/sched.h > +++ b/kernel/sched/sched.h > @@ -3758,8 +3758,10 @@ static __always_inline void mm_unset_cid_on_task(s= truct task_struct *t) > static __always_inline void mm_drop_cid_on_cpu(struct mm_struct *mm, str= uct mm_cid_pcpu *pcp) > { > /* Clear the ONCPU bit, but do not set UNSET in the per CPU storage */ > - pcp->cid =3D cpu_cid_to_cid(pcp->cid); > - mm_drop_cid(mm, pcp->cid); > + if (cid_on_cpu(pcp->cid)) { > + pcp->cid =3D cpu_cid_to_cid(pcp->cid); > + mm_drop_cid(mm, pcp->cid); > + } > } > =20 > static inline unsigned int __mm_get_cid(struct mm_struct *mm, unsigned i= nt max_cids) >=20 Thomas, the fix patch worked! I applied the patch on top of v6.19 kernel, t= hen the KASAN is no longer observed. I confirmed it with my two test nodes. Tha= nk you very much for the swift fix :) In case the patch will be posted as a formal one, Tested-by: Shin'ichiro Kawasaki P.S. I stop working here tonight. If my response will be required, I will d= o so tomorrow.=