Re: [PATCH v2 0/2] Drivers: hv: util: Two fixes in util_probe()

From: Wei Liu
Date: Sat Dec 07 2024 - 02:03:03 EST


On Wed, Nov 06, 2024 at 07:42:45AM -0800, mhkelley58@xxxxxxxxx wrote:
> From: Michael Kelley <mhklinux@xxxxxxxxxxx>
>
> Patch 1 fixes util_probe() to not force the error return value to
> ENODEV when the util_init function fails -- just return the error
> code from util_init so the real error code is displayed in messages.
>
> Patch 2 fixes a more serious race condition between initialization
> of the VMBus channel and initial operations of the user space
> daemons for KVP and VSS. The fix reorders the initialization in
> util_probe() so the race condition can't happen.
>
> The two fixes are functionally independent, but Patch 2 introduces
> the util_init_transport function that parallels the existing code
> for the util_init function. Doing Patch 1 first avoids an
> inconsistency in the error handling in similar code for these two
> parts of util_probe().
>
> This series is v2 of a single patch first posted by Dexuan Cui
> to fix the race condition.[1] I've taken over the patch per
> discussion with Dexuan.
>
> [1] https://lore.kernel.org/linux-hyperv/20240909164719.41000-1-decui@xxxxxxxxxxxxx/
>
> Michael Kelley (2):
> Drivers: hv: util: Don't force error code to ENODEV in util_probe()
> Drivers: hv: util: Avoid accessing a ringbuffer not initialized yet

Acked-by: Wei Liu <wei.liu@xxxxxxxxxx>