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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.1 (3.54.1-1.fc41) MIME-Version: 1.0 X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: F3C0F20003 X-Stat-Signature: 31zbz78runnrkc38163xo6zgszxhn8zu X-HE-Tag: 1738763770-792416 X-HE-Meta: U2FsdGVkX1/0J0r9CUAk1wLZ20UtCR7zqjt7JOqxcUUadgMcvo01z3VFQ1vv1uZ2h3HZUNXpnw/56gUA/+rp7iYNfC7vKMaGZU4bKj1laSqT055RCJPvvXWp+Y2C6esg7OnLl3FG/CAEPgL1UlhM9a5ySJjRmicWNk6DfZaa2LI/i7qxBF4KD8zVaZ5K0YjoVPJm5eG3X/S9oNBuT1a4JKF1NrMiutNecwsbH4inf3zCT+HuRT9nGKOlEMdw62kCdVmxPGSel8qY94qM4EtUG3ksU9MIKhRJ1roZ8VQv4I9sxKRQoZKLukmS+oy7MZCubAZtCKNNB2NEYd9bKIvw9uL6aNaPM1ZNm5E8aNTfccpmFzhypeZKFRzoAhBBM5SFiTJbjNgTwm9Ux4M3Tf84g/XYolvcKo8zBiUsiHVZXBZxMGKq/fX+kYbu12WVcervcsygemrQzD7KIoOKcqx2K2H3wC4sq98dY0WMIrLy+6Y+hDXmrTVajdBgbggvyYgMk9BzrrBIDwgwrhW8I2M5asGfbH4fqnUEHDsOidjAaKQ3i8VJOm2++5Aa/8wD45qyzol8meE5/7UzAMWiB56eFljcZAWqC+UDFRLYz9KFfo3a5xkfAokz+1wTunkguKZC87r2roerruBqJ7FVdpAspNrwjLwAkm99d2U3dMdV+zQuzpOT3QknlOJkK0cPZhSPJmu2DsKCOe7t9tJy5pzBHMVnsj831dSSf636nmyvQH7YFn9bNnK3oQ7Gcj99PMCgRk3I4H+8a+4B/0vLtW9GO/cjyNurwN2P0ZdiLAV6ac8rHNWNCc5yVsZT+onONBBTzHGg0gE7lREShzREJMy4TIHrKXda/yWgRUDRgbsvfj8TNjDMvMgzWbD0qEdiu7xM4vEc1oOKfU4LbX/M+L1WH6AWoGOjNJvxXBe6GC2VIZj1XO+vFlEKTH2/mb84z4kF6vqFcyIwtAzHcn+8rDf 9W+vz7ij W58fqVvtGT7YfZK+9f72N+zB1pSPXdBee4xRvtvwV5M8XBB0K3+yE72hacbFEjhrTWEKPNwIro72pkZFQ7t39RIaBaxDgnvxcqucdTTZB98frbl1WojQImONtyHOkshJeWlc5UZzgDU6TQfAFjQP7f8mY7zoqi/qWC4cEs068IZ5CwyIBzUgfnGW856E6MzZOGgVRHWudb3yQpTPddpOLfto5a8xReYl7gI3QpbDWEfMBcqdMR1CkZFRj1UYo5jvl9YE1pUJWlpHp+HxLK07FRbI5AGw3/Fb6yFwLqEQowSaed32HUaD0/YexxmLmuVy0NgUGy2lhz4PFuf0hQ+6fMBMk6fhiqsVQgKKfc79J1ey7Qgw0p2IpAwOn7Gyui3sYfYGPXJQyaDb6Ne9GGjf1NdmclaAvxcCcrvImgQqDuRwFJ5E= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, 2025-02-05 at 13:20 +0100, Peter Zijlstra wrote: > On Tue, Feb 04, 2025 at 08:39:52PM -0500, Rik van Riel wrote: >=20 > > diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c > > index 6cf881a942bb..02e1f5c5bca3 100644 > > --- a/arch/x86/mm/tlb.c > > +++ b/arch/x86/mm/tlb.c > > @@ -1000,8 +1000,13 @@ static struct flush_tlb_info > > *get_flush_tlb_info(struct mm_struct *mm, > > =C2=A0 BUG_ON(this_cpu_inc_return(flush_tlb_info_idx) !=3D 1); > > =C2=A0#endif > > =C2=A0 > > - info->start =3D start; > > - info->end =3D end; > > + /* > > + * Round the start and end addresses to the page size > > specified > > + * by the stride shift. This ensures partial pages at the > > end of > > + * a range get fully invalidated. > > + */ > > + info->start =3D round_down(start, 1 << > > stride_shift); > > + info->end =3D round_up(end, 1 << > > stride_shift); > > =C2=A0 info->mm =3D mm; > > =C2=A0 info->stride_shift =3D stride_shift; > > =C2=A0 info->freed_tables =3D freed_tables; >=20 > Rather than doing this; should we not fix whatever dodgy users are > feeding us non-page-aligned addresses for invalidation? >=20 The best way to do that would probably be by adding a WARN_ON_ONCE here if the value of either start or end changed, not by merging code that will trigger kernel crashes - even if the bug is elsewhere. I would be happy to add a WARN_ON_ONCE either in a next version, or in a follow-up patch, whichever is more convenient for you. --=20 All Rights Reversed.