From: Joerg Roedel <joro@8bytes.org>
To: Lennert Buytenhek <buytenh@wantstofly.org>
Cc: iommu@lists.linux-foundation.org
Subject: Re: [PATCH,RFC] iommu/amd: Recover from event log overflow
Date: Tue, 28 Sep 2021 10:45:30 +0200 [thread overview]
Message-ID: <YVLWKtc3ZaL5fvq9@8bytes.org> (raw)
In-Reply-To: <YSEaIloMR1VAMXLo@wantstofly.org>
Hi Lennert,
On Sat, Aug 21, 2021 at 06:22:10PM +0300, Lennert Buytenhek wrote:
> +/*
> + * This function restarts event logging in case the IOMMU experienced
> + * an event log buffer overflow.
> + */
> +void amd_iommu_restart_event_logging(struct amd_iommu *iommu)
> +{
> + iommu_feature_disable(iommu, CONTROL_EVT_LOG_EN);
> + iommu_feature_enable(iommu, CONTROL_EVT_LOG_EN);
> +}
A few more things need to happen here. First of all head and tail are
likely equal when the event buffer overflows, so the events will not be
polled and reported.
And next it is also a good idea to reset the head and tail pointers of
the event log to 0 after the events have been polled.
Regards,
Joerg
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next prev parent reply other threads:[~2021-09-28 8:46 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-21 15:22 [PATCH,RFC] iommu/amd: Recover from event log overflow Lennert Buytenhek
2021-09-28 8:45 ` Joerg Roedel [this message]
2021-09-30 13:45 ` Lennert Buytenhek
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