Messages in this thread | | | Date | Fri, 30 Mar 2007 12:47:47 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH 2.6.21-rc5] Flush MSI-X table writes (rev 3) |
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On Fri, 30 Mar 2007 13:04:02 -0600 ebiederm@xmission.com (Eric W. Biederman) wrote:
> Mitch Williams <mitch.a.williams@intel.com> writes: > > > This patch fixes a kernel bug which is triggered when using the > > irqbalance daemon with MSI-X hardware. > > > > Because both MSI-X interrupt messages and MSI-X table writes are posted, > > it's possible for them to cross while in-flight. This results in > > interrupts being received long after the kernel thinks they're disabled, > > and in interrupts being sent to stale vectors after rebalancing. > > > > This patch performs a read flush after writes to the MSI-X table for > > mask and unmask operations. Since the SMP affinity is set while > > the interrupt is masked, and since it's unmasked immediately after, > > no additional flushes are required in the various affinity setting > > routines. > > > > This patch has been validated with (unreleased) network hardware which > > uses MSI-X. > > > > Revised with input from Eric Biederman. > > Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Did we end up deciding whether this is (needed*safe) enough for 2.6.21? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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