Message-ID: <sashiko-outbox-204466@kernel.org>
From: sashiko-bot@kernel.org
Subject: Re: [PATCH v3 2/4] x86/vmware: Add a bounded panic log sender
Reply-To: sashiko-reviews@lists.linux.dev
To: "Zack Rusin" <zack.rusin@broadcom.com>, "Andrew Morton" <akpm@linux-foundation.org>, "Petr
 Mladek" <pmladek@suse.com>, "Baoquan He" <baoquan.he@linux.dev>, "Mike
 Rapoport" <rppt@kernel.org>, "Pasha Tatashin" <pasha.tatashin@soleen.com>, "Pratyush
 Yadav" <pratyush@kernel.org>, "Dave Young" <ruirui.yang@linux.dev>
Cc: "Borislav Petkov" <bp@alien8.de>, "Ajay Kaher" <ajay.kaher@broadcom.com>, "Alexey
 Makhalov" <alexey.makhalov@broadcom.com>, x86@kernel.org, "Joel Granados" <joel.granados@kernel.org>, "Thomas
 Gleixner" <tglx@kernel.org>, "Ingo Molnar" <mingo@redhat.com>, "Dave Hansen" <dave.hansen@linux.intel.com>, "H.
 Peter Anvin" <hpa@zytor.com>, virtualization@lists.linux.dev, bcm-kernel-feedback-list@broadcom.com, "John
 Ogness" <john.ogness@linutronix.de>, "Steven Rostedt" <rostedt@goodmis.org>, "Sergey
 Senozhatsky" <senozhatsky@chromium.org>, "Kees Cook" <kees@kernel.org>, "Jonathan
 Corbet" <corbet@lwn.net>, "Bo Gan" <bo.gan@broadcom.com>, "Brennan
 Lamoreaux" <brennan.lamoreaux@broadcom.com>, kexec@lists.infradead.org, "Guilherme
 G. Piccoli" <gpiccoli@igalia.com>, "Maaz Mombasawala" <maaz.mombasawala@broadcom.com>, "Shuah
 Khan" <skhan@linuxfoundation.org>, "Randy Dunlap" <rdunlap@infradead.org>, "Stephen
 Brennan" <stephen.s.brennan@oracle.com>, "Michael Kelley" <mhklinux@outlook.com>, "Ian
 Forbes" <ian.forbes@broadcom.com>, "Bradley Morgan" <brads@mainlining.org>, "Michael
 S. Tsirkin" <mst@redhat.com>, "Eugenio Perez" <eperezma@redhat.com>
In-Reply-To: <b4befd89cc0b5844f499606b7d42f13cdb37046a.1794201807.git.zack.rusin@broadcom.com>
References: <cover.1794201807.git.zack.rusin@broadcom.com>
 <b4befd89cc0b5844f499606b7d42f13cdb37046a.1794201807.git.zack.rusin@broadcom.com>
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Date: Mon, 09 Nov 2026 05:57:19 +0000
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> A VMware guest may be unable to save its own logs after a crash. Copy
> the newest kernel log records to the host's vmware.log before kdump,
> so they remain available if the capture kernel fails.
>=20
> Register the sender on the platform panic notifier list and send the
> log through the low-bandwidth register interface. Allocate a fixed
> 8 KiB buffer during early init; 4 KiB can lose useful stack-trace
> context. The callback allocates no memory and emits no printk
> messages. Limit the transfer to the buffer size and make at most three
> attempts, retrying only if a VM checkpoint interrupts the transfer.
>=20
> Enable logging by default only in guests without memory encryption;
> encrypted guests should send their log to the host only when an
> administrator opts in. The copy is best-effort diagnostics; kdump does
> not depend on it succeeding.
>=20
> Suggested-by: Michael Kelley <mhklinux@outlook.com>
> Link: https://lore.kernel.org/r/SN6PR02MB41574A11D309A0530C63E0FED4842@SN=
6PR02MB4157.namprd02.prod.outlook.com
> Link: https://lore.kernel.org/r/20260309235250.2611115-3-alexey.makhalov@=
broadcom.com
> Co-developed-by: Bo Gan <bo.gan@broadcom.com>
> Signed-off-by: Bo Gan <bo.gan@broadcom.com>
> Co-developed-by: Alexey Makhalov <alexey.makhalov@broadcom.com>
> Signed-off-by: Alexey Makhalov <alexey.makhalov@broadcom.com>
> Signed-off-by: Zack Rusin <zack.rusin@broadcom.com>

Sashiko has reviewed this patch and found no issues.

--=20
Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/cover.1794201807.gi=
t.zack.rusin@broadcom.com?part=3D2