From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Date: Mon, 01 Jun 2009 07:45:57 +0000 Subject: Re: [PATCH] qemu-kvm: Flush icache after dma operations for ia64 Message-Id: <4A238735.1050006@redhat.com> List-Id: References: <706158FABBBA044BAD4FE898A02E4BC236B1935F@pdsmsx503.ccr.corp.intel.com> In-Reply-To: <706158FABBBA044BAD4FE898A02E4BC236B1935F@pdsmsx503.ccr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kvm-ia64@vger.kernel.org Zhang, Xiantao wrote: > Avi Kivity wrote: > >> Jes Sorensen wrote: >> >>> Ok, >>> >>> Trying once more. After spending a couple of hours trying to follow >>> the QEMU dma codeflow, I have convinced myself Avi is right and those >>> two functions don't need to do the flushing as they all end up >>> calling dma_bdrv_cb() which calls dma_brdv_unmap(). I have added a >>> couple comments to the code, which will hopefully save the next >>> person the 'pleasure' of trying to figure out this too. >>> >>> >> It looks right to me. Xiantao? >> > > Fine to me. But seems the change in qemu_iovec_from_buffer is lost in this patch or that change is also not unnecessary ? > I think the fixed unmap handles that case. Can you test to make sure? -- Do not meddle in the internals of kernels, for they are subtle and quick to panic.