similar to: [PATCH] virtio_balloon: prevent pfn array overflow

Everything should be LE when using virtio-1, but the linux balloon driver does not seem to care about that. Cc: stable at vger.kernel.org Reported-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/virtio/virtio_balloon.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git

Everything should be LE when using virtio-1, but the linux balloon driver does not seem to care about that. Cc: stable at vger.kernel.org Reported-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/virtio/virtio_balloon.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git

From: "Michael S. Tsirkin" <mst at redhat.com> [ Upstream commit 6e9826e77249355c09db6ba41cd3f84e89f4b614 ] Make sure, at build time, that pfn array is big enough to hold a single page. It happens to be true since the PAGE_SHIFT value at the moment is 20, which is 1M - exactly 256 4K balloon pages. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: David

fill_balloon doing memory allocations under balloon_lock can cause a deadlock when leak_balloon is called from virtballoon_oom_notify and tries to take same lock. To fix, split page allocation and enqueue and do allocations outside the lock. Here's a detailed analysis of the deadlock by Tetsuo Handa: In leak_balloon(), mutex_lock(&vb->balloon_lock) is called in order to serialize

fill_balloon doing memory allocations under balloon_lock can cause a deadlock when leak_balloon is called from virtballoon_oom_notify and tries to take same lock. To fix, split page allocation and enqueue and do allocations outside the lock. Here's a detailed analysis of the deadlock by Tetsuo Handa: In leak_balloon(), mutex_lock(&vb->balloon_lock) is called in order to serialize

This patch series intends to summarize the recent contributions made by Michael S. Tsirkin, Tetsuo Handa, Michal Hocko etc. via reporting and discussing the related deadlock issues on the mailinglist. Please check each patch for details. >From a high-level point of view, this patch series achieves: 1) eliminate the deadlock issue fundamentally caused by the inability to run leak_balloon and

This patch series intends to summarize the recent contributions made by Michael S. Tsirkin, Tetsuo Handa, Michal Hocko etc. via reporting and discussing the related deadlock issues on the mailinglist. Please check each patch for details. >From a high-level point of view, this patch series achieves: 1) eliminate the deadlock issue fundamentally caused by the inability to run leak_balloon and

Wei Wang wrote: > The balloon_lock was used to synchronize the access demand to elements > of struct virtio_balloon and its queue operations (please see commit > e22504296d). This prevents the concurrent run of the leak_balloon and > fill_balloon functions, thereby resulting in a deadlock issue on OOM: > > fill_balloon: take balloon_lock and wait for OOM to get some memory; >

Wei Wang wrote: > The balloon_lock was used to synchronize the access demand to elements > of struct virtio_balloon and its queue operations (please see commit > e22504296d). This prevents the concurrent run of the leak_balloon and > fill_balloon functions, thereby resulting in a deadlock issue on OOM: > > fill_balloon: take balloon_lock and wait for OOM to get some memory; >

From: "Michael S. Tsirkin" <mst at redhat.com> [ Upstream commit 6e9826e77249355c09db6ba41cd3f84e89f4b614 ] Make sure, at build time, that pfn array is big enough to hold a single page. It happens to be true since the PAGE_SHIFT value at the moment is 20, which is 1M - exactly 256 4K balloon pages. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: David

From: "Michael S. Tsirkin" <mst at redhat.com> [ Upstream commit 6e9826e77249355c09db6ba41cd3f84e89f4b614 ] Make sure, at build time, that pfn array is big enough to hold a single page. It happens to be true since the PAGE_SHIFT value at the moment is 20, which is 1M - exactly 256 4K balloon pages. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: David

From: "Michael S. Tsirkin" <mst at redhat.com> [ Upstream commit 6e9826e77249355c09db6ba41cd3f84e89f4b614 ] Make sure, at build time, that pfn array is big enough to hold a single page. It happens to be true since the PAGE_SHIFT value at the moment is 20, which is 1M - exactly 256 4K balloon pages. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: David

There are cases that users want to shrink balloon pages after the pagecache depleted. The conservative_shrinker lets the shrinker shrink balloon pages when all the pagecache has been reclaimed. Signed-off-by: Wei Wang <wei.w.wang at intel.com> --- drivers/virtio/virtio_balloon.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git

There are cases that users want to shrink balloon pages after the pagecache depleted. The conservative_shrinker lets the shrinker shrink balloon pages when all the pagecache has been reclaimed. Signed-off-by: Wei Wang <wei.w.wang at intel.com> --- drivers/virtio/virtio_balloon.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git

Wei Wang wrote: > >> @@ -162,20 +160,20 @@ static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > >> msleep(200); > >> break; > >> } > >> - set_page_pfns(vb, vb->pfns + vb->num_pfns, page); > >> - vb->num_pages += VIRTIO_BALLOON_PAGES_PER_PAGE; > >> + set_page_pfns(vb, pfns + num_pfns, page);

Wei Wang wrote: > >> @@ -162,20 +160,20 @@ static unsigned fill_balloon(struct virtio_balloon *vb, size_t num) > >> msleep(200); > >> break; > >> } > >> - set_page_pfns(vb, vb->pfns + vb->num_pfns, page); > >> - vb->num_pages += VIRTIO_BALLOON_PAGES_PER_PAGE; > >> + set_page_pfns(vb, pfns + num_pfns, page);

This patch series enhances the existing virtio-balloon with the following new features: 1) fast ballooning: transfer ballooned pages between the guest and host in chunks, instead of one by one; and 2) cmdq: a new virtqueue to send commands between the device and driver. Currently, it supports commands to report memory stats (replace the old statq mechanism) and report guest unused pages. Liang Li

This patch series enhances the existing virtio-balloon with the following new features: 1) fast ballooning: transfer ballooned pages between the guest and host in chunks, instead of one by one; and 2) cmdq: a new virtqueue to send commands between the device and driver. Currently, it supports commands to report memory stats (replace the old statq mechanism) and report guest unused pages. Liang Li

This patch series implements the follow two things: 1) Optimization of balloon page transfer: instead of transferring balloon pages to host one by one, the new mechanism transfers them in chunks. 2) A mechanism to report info of guest unused pages: the pages have been unused at some time between when host sent command and when guest reported them. Host uses that by tracking memory changes and

This patch series implements the follow two things: 1) Optimization of balloon page transfer: instead of transferring balloon pages to host one by one, the new mechanism transfers them in chunks. 2) A mechanism to report info of guest unused pages: the pages have been unused at some time between when host sent command and when guest reported them. Host uses that by tracking memory changes and