From: no-reply@sashiko.virtuozzo.com
To: svt-core@virtuozzo.com,
Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
Cc: andrey.drobyshev@virtuozzo.com
Subject: Re: [PATCH QEMU HCI-8.1 v3 24/28] VZ: migration/cpr-exec: abort cpr-exec if memory can't be preserved
Date: Fri, 16 Oct 2026 15:55:09 +0000 [thread overview]
Message-ID: <010701a1456ca208-a75e4f2f-70c6-4415-8766-ff96e40e407d-000000@eu-central-1.amazonses.com> (raw)
In-Reply-To: <20261016-vfio_v1-v3-24-47487cb5a8e5@virtuozzo.com>
> cpr_exec_cb() marks all saved ramblocks with MADV_DOEXEC before exec, but
> ignores the result. If madvise() fails for some block, the walk stops
> there and the remaining blocks are not marked, yet execvp() still runs.
> The new QEMU then reuses addresses of guest RAM that wasn't preserved,
> and the guest is lost.
>
> Treat that as a failed cpr-exec: go to the same failure path as when
> execvp() fails, so the VM keeps running in the old QEMU.
>
> On that path also clear MADV_DOEXEC from all saved ramblocks again, just
> like the preserved fds get close-on-exec back.
>
> Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
Sashiko has reviewed this patch and found no issues. It looks great!
--
Sashiko AI review · https://sashiko.vzint.dev/#/patchset/20261016-vfio_v1-v3-0-47487cb5a8e5@virtuozzo.com?part=24
next prev parent reply other threads:[~2026-10-16 15:55 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-16 15:25 [PATCH QEMU HCI-8.1 v3 00/28] vfio: support qemu-update with passed through GPU's and vGPU's #VSTOR-103860 Andrey Drobyshev
2026-10-16 15:25 ` [PATCH QEMU HCI-8.1 v3 01/28] VZ: migration/cpr-exec: fix Error leak in preserve_ram() Andrey Drobyshev
2026-10-16 15:28 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 02/28] migration/cpr-exec: restore RAM write access if exec fails Andrey Drobyshev
2026-10-16 15:28 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 03/28] vfio/region: create BAR dma-bufs with O_CLOEXEC Andrey Drobyshev
2026-10-16 15:30 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 04/28] migration: Plug memory leaks after migrate_set_error() Andrey Drobyshev
2026-10-16 15:29 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 05/28] hw/vfio: Fix liveness check in vfio_connect_kvm_msi_virq() Andrey Drobyshev
2026-10-16 15:30 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 06/28] vfio/pci: Reject invalid MSI-X Table and PBA BIR values Andrey Drobyshev
2026-10-16 15:30 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 07/28] vfio/pci: Fix information leak in vfio_rom_read() Andrey Drobyshev
2026-10-16 15:31 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 08/28] vfio/pci: Initialize rom_read_failed in vfio_pci_load_rom() Andrey Drobyshev
2026-10-16 15:32 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 09/28] vfio/pci: Grow buffer in vfio_pci_host_match() Andrey Drobyshev
2026-10-16 15:31 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 10/28] q35: Fix migration of SMRAM state Andrey Drobyshev
2026-10-16 15:33 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 11/28] migration: ensure APIC is loaded prior to VFIO PCI devices Andrey Drobyshev
2026-10-16 15:32 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 12/28] migration: Fix regression of passing error_fatal into vmstate_load_state() Andrey Drobyshev
2026-10-16 15:35 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 13/28] migration: vmstate_save_state_v: fix double error_setg Andrey Drobyshev
2026-10-16 15:38 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 14/28] migration: yank: Move register instance earlier Andrey Drobyshev
2026-10-16 15:41 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 15/28] migration: Free cpr-transfer MigrationAddress along with gsource Andrey Drobyshev
2026-10-16 15:39 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 16/28] migration: Move CPR HUP watch to cpr-transfer.c Andrey Drobyshev
2026-10-16 15:40 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 17/28] migration: Fix crash on second migration when cancel early Andrey Drobyshev
2026-10-16 15:44 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 18/28] kvm: tolerate ioctls after kvm_close() Andrey Drobyshev
2026-10-16 15:44 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 19/28] kvm: fix coalesced MMIO flush racing with kvm_close() Andrey Drobyshev
2026-10-16 15:46 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 20/28] migration/cpr: add cpr_is_in_progress() Andrey Drobyshev
2026-10-16 15:46 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 21/28] vfio/migration: don't migrate device state during CPR Andrey Drobyshev
2026-10-16 15:55 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 22/28] vfio/listener: skip dirty page tracking " Andrey Drobyshev
2026-10-16 15:50 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 23/28] VZ: vfio/cpr: don't close KVM on cpr-exec Andrey Drobyshev
2026-10-16 15:52 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 24/28] VZ: migration/cpr-exec: abort cpr-exec if memory can't be preserved Andrey Drobyshev
2026-10-16 15:55 ` no-reply [this message]
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 25/28] VZ: migration/cpr-exec: take the vhost-net devices back if exec fails Andrey Drobyshev
2026-10-16 15:58 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 26/28] VZ: migration/cpr-exec: don't exec if a vhost-net device can't be released Andrey Drobyshev
2026-10-16 15:56 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 27/28] VZ: vfio/region: preserve BAR mappings across cpr-exec #VSTOR-103860 Andrey Drobyshev
2026-10-16 16:02 ` no-reply
2026-10-16 15:26 ` [PATCH QEMU HCI-8.1 v3 28/28] VZ: migration/cpr-exec: allow cpr-exec with VFIO devices #VSTOR-103860 Andrey Drobyshev
2026-10-16 15:59 ` no-reply
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