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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.1 (3.54.1-1.fc41) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Sender: riel@surriel.com On Fri, 2025-01-17 at 19:23 +0000, Michael Kelley wrote: > From: riel@surriel.com=C2=A0 Sent: Wednesday, January > 15, 2025 6:30 PM > >=20 > > - info =3D get_flush_tlb_info(NULL, start, end, 0, > > false, > > - =C2=A0 TLB_GENERATION_INVALID); > > + guard(preempt)(); > > + > > + info =3D get_flush_tlb_info(NULL, start, end, PAGE_SHIFT, > > false, > > + =C2=A0 TLB_GENERATION_INVALID); > >=20 > > + if (end =3D=3D TLB_FLUSH_ALL) >=20 > This needs to test "info->end", not "end". >=20 > In my VM on Hyper-V *without* INVLPGB support, the bug causes > boot to hang as it tries to individually flush each page in the > [0, TLB_FLUSH_ALL] range. :-) Ohhhh, good catch. I guess on bare metal the automatic tests that run on every kernel build didn't notice the slower boot, because it's not as severe of an impact as in a virtual machine. --=20 All Rights Reversed.