search for: flush_dcache_pages

From: "Michael S. Tsirkin" <mst at redhat.com> Date: Mon, 11 Mar 2019 09:59:28 -0400 > On Mon, Mar 11, 2019 at 03:13:17PM +0800, Jason Wang wrote: >> >> On 2019/3/8 ??10:12, Christoph Hellwig wrote: >> > On Wed, Mar 06, 2019 at 02:18:07AM -0500, Jason Wang wrote: >> > > This series tries to access virtqueue metadata through kernel virtual

From: "Michael S. Tsirkin" <mst at redhat.com> Date: Mon, 11 Mar 2019 09:59:28 -0400 > On Mon, Mar 11, 2019 at 03:13:17PM +0800, Jason Wang wrote: >> >> On 2019/3/8 ??10:12, Christoph Hellwig wrote: >> > On Wed, Mar 06, 2019 at 02:18:07AM -0500, Jason Wang wrote: >> > > This series tries to access virtqueue metadata through kernel virtual

On 2019/3/12 ??1:14, James Bottomley wrote: > On Tue, 2019-03-12 at 10:59 +0800, Jason Wang wrote: >> On 2019/3/12 ??2:14, David Miller wrote: >>> From: "Michael S. Tsirkin" <mst at redhat.com> >>> Date: Mon, 11 Mar 2019 09:59:28 -0400 >>> >>>> On Mon, Mar 11, 2019 at 03:13:17PM +0800, Jason Wang wrote: >>>>> On

On Tue, Mar 12, 2019 at 10:59:09AM +0800, Jason Wang wrote: > > On 2019/3/12 ??2:14, David Miller wrote: > > From: "Michael S. Tsirkin" <mst at redhat.com> > > Date: Mon, 11 Mar 2019 09:59:28 -0400 > > > > > On Mon, Mar 11, 2019 at 03:13:17PM +0800, Jason Wang wrote: > > > > On 2019/3/8 ??10:12, Christoph Hellwig wrote: > > >

On Tue, Mar 12, 2019 at 10:59:09AM +0800, Jason Wang wrote: > > On 2019/3/12 ??2:14, David Miller wrote: > > From: "Michael S. Tsirkin" <mst at redhat.com> > > Date: Mon, 11 Mar 2019 09:59:28 -0400 > > > > > On Mon, Mar 11, 2019 at 03:13:17PM +0800, Jason Wang wrote: > > > > On 2019/3/8 ??10:12, Christoph Hellwig wrote: > > >

We set dirty bit through setting up kmaps and access them through kernel virtual address, this may result alias in virtually tagged caches that require a dcache flush afterwards. Cc: Christoph Hellwig <hch at infradead.org> Cc: James Bottomley <James.Bottomley at HansenPartnership.com> Cc: Andrea Arcangeli <aarcange at redhat.com> Fixes: 3a4d5c94e9593 ("vhost_net: a

We set dirty bit through setting up kmaps and access them through kernel virtual address, this may result alias in virtually tagged caches that require a dcache flush afterwards. Cc: Christoph Hellwig <hch at infradead.org> Cc: James Bottomley <James.Bottomley at HansenPartnership.com> Cc: Andrea Arcangeli <aarcange at redhat.com> Fixes: 3a4d5c94e9593 ("vhost_net: a

On Tue, Mar 12, 2019 at 08:46:50AM -0700, James Bottomley wrote: > On Tue, 2019-03-12 at 07:54 -0400, Michael S. Tsirkin wrote: > > On Tue, Mar 12, 2019 at 03:17:00PM +0800, Jason Wang wrote: > > > > > > On 2019/3/12 ??????11:52, Michael S. Tsirkin wrote: > > > > On Tue, Mar 12, 2019 at 10:59:09AM +0800, Jason Wang wrote: > [...] > > > At least

On Tue, Mar 12, 2019 at 02:19:15PM -0700, James Bottomley wrote: > I mean in the sequence > > flush_dcache_page(page); > flush_dcache_page(page); > > The first flush_dcache_page did all the work and the second it a > tightly pipelined no-op. That's what I mean by there not really being > a double hit. Ok I wasn't sure it was clear there was a double (profiling)

On Wed, Mar 13, 2019 at 09:37:08AM -0700, James Bottomley wrote: > On Wed, 2019-03-13 at 09:05 -0700, Christoph Hellwig wrote: > > On Tue, Mar 12, 2019 at 01:53:37PM -0700, James Bottomley wrote: > > > I've got to say: optimize what? What code do we ever have in the > > > kernel that kmap's a page and then doesn't do anything with it? You > > > can

This problem is found in meego testing: http://bugs.meego.com/show_bug.cgi?id=6672 A file in btrfs is mmaped and the mmaped buffer is passed to pwrite to write to the same page of the same file. In btrfs_file_aio_write(), the pages is locked by prepare_pages(). So when btrfs_copy_from_user() is called, page fault happens and the same page needs to be locked again in filemap_fault(). The fix is to

On 2019/3/12 ??2:14, David Miller wrote: > From: "Michael S. Tsirkin" <mst at redhat.com> > Date: Mon, 11 Mar 2019 09:59:28 -0400 > >> On Mon, Mar 11, 2019 at 03:13:17PM +0800, Jason Wang wrote: >>> On 2019/3/8 ??10:12, Christoph Hellwig wrote: >>>> On Wed, Mar 06, 2019 at 02:18:07AM -0500, Jason Wang wrote: >>>>> This series tries

On 2019/3/12 ??11:52, Michael S. Tsirkin wrote: > On Tue, Mar 12, 2019 at 10:59:09AM +0800, Jason Wang wrote: >> On 2019/3/12 ??2:14, David Miller wrote: >>> From: "Michael S. Tsirkin" <mst at redhat.com> >>> Date: Mon, 11 Mar 2019 09:59:28 -0400 >>> >>>> On Mon, Mar 11, 2019 at 03:13:17PM +0800, Jason Wang wrote: >>>>>

On Tue, Apr 09, 2019 at 12:16:47PM +0800, Jason Wang wrote: > We set dirty bit through setting up kmaps and access them through > kernel virtual address, this may result alias in virtually tagged > caches that require a dcache flush afterwards. > > Cc: Christoph Hellwig <hch at infradead.org> > Cc: James Bottomley <James.Bottomley at HansenPartnership.com> > Cc:

When buffered write fails to copy data into underlying page cache page, ocfs2_write_end_nolock() just zeroes out and dirties the page. This can leave dirty page beyond EOF and if page writeback tries to write this page before write succeeds and expands i_size, page gets into inconsistent state where page dirty bit is clear but buffer dirty bits stay set resulting in page data never getting written

On Tue, Mar 12, 2019 at 01:53:37PM -0700, James Bottomley wrote: > I've got to say: optimize what? What code do we ever have in the > kernel that kmap's a page and then doesn't do anything with it? You can > guarantee that on kunmap the page is either referenced (needs > invalidating) or updated (needs flushing). The in-kernel use of kmap is > always > > kmap

tree: https://kernel.googlesource.com/pub/scm/linux/kernel/git/mst/vhost.git linux-next head: c5db5a8d998da36ada7287aa53b4ed501a0a2b2b commit: b1b0d638e6f93b91cf34585350bb00035d066989 [13/15] mm: Introduce Reported pages config: ia64-defconfig (attached as .config) compiler: ia64-linux-gcc (GCC) 7.4.0 reproduce: wget

The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable at vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/

The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable at vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/

...mem += vec.bv_len; + transfered += vec.bv_len; } bio_endio(bio, 0); } diff --git a/block/blk-core.c b/block/blk-core.c index 5c2ab2c..5da8e90 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -2746,10 +2746,10 @@ void blk_rq_bio_prep(struct request_queue *q, struct request *rq, void rq_flush_dcache_pages(struct request *rq) { struct req_iterator iter; - struct bio_vec *bvec; + struct bio_vec bvec; rq_for_each_segment(bvec, rq, iter) - flush_dcache_page(bvec->bv_page); + flush_dcache_page(bvec.bv_page); } EXPORT_SYMBOL_GPL(rq_flush_dcache_pages); #endif diff --git a/block/blk-merge.c...