similar to: [PATCH] net: don't use kvzalloc for DMA memory

On 04/18/2018 09:44 AM, Mikulas Patocka wrote: > > > On Wed, 18 Apr 2018, Eric Dumazet wrote: > >> >> >> On 04/18/2018 07:34 AM, Mikulas Patocka wrote: >>> The patch 74d332c13b21 changes alloc_netdev_mqs to use vzalloc if kzalloc >>> fails (later patches change it to kvzalloc). >>> >>> The problem with this is that if the vzalloc

On Wed, 18 Apr 2018, David Miller wrote: > From: Mikulas Patocka <mpatocka at redhat.com> > Date: Wed, 18 Apr 2018 12:44:25 -0400 (EDT) > > > The structure net_device is followed by arbitrary driver-specific data > > (accessible with the function netdev_priv). And for virtio-net, these > > driver-specific data must be in DMA memory. > > And we are saying

On Thu, Apr 19, 2018 at 12:12:38PM -0400, Mikulas Patocka wrote: > > > On Wed, 18 Apr 2018, Mikulas Patocka wrote: > > > > > > > On Wed, 18 Apr 2018, David Miller wrote: > > > > > From: Mikulas Patocka <mpatocka at redhat.com> > > > Date: Wed, 18 Apr 2018 12:44:25 -0400 (EDT) > > > > > > > The structure

On 04/25/2018 01:02 PM, Mikulas Patocka wrote: > > > From: Mikulas Patocka <mpatocka at redhat.com> > Subject: [PATCH v4] fault-injection: introduce kvmalloc fallback options > > This patch introduces a fault-injection option "kvmalloc_fallback". This > option makes kvmalloc randomly fall back to vmalloc. > > Unfortunatelly, some kernel code has bugs

On 04/25/2018 01:02 PM, Mikulas Patocka wrote: > > > From: Mikulas Patocka <mpatocka at redhat.com> > Subject: [PATCH v4] fault-injection: introduce kvmalloc fallback options > > This patch introduces a fault-injection option "kvmalloc_fallback". This > option makes kvmalloc randomly fall back to vmalloc. > > Unfortunatelly, some kernel code has bugs

On Tue 24-04-18 11:30:40, Mikulas Patocka wrote: > > > On Tue, 24 Apr 2018, Michal Hocko wrote: > > > On Mon 23-04-18 20:25:15, Mikulas Patocka wrote: > > > > > Fixing __vmalloc code > > > is easy and it doesn't require cooperation with maintainers. > > > > But it is a hack against the intention of the scope api. > > It is not!

On Tue 24-04-18 11:30:40, Mikulas Patocka wrote: > > > On Tue, 24 Apr 2018, Michal Hocko wrote: > > > On Mon 23-04-18 20:25:15, Mikulas Patocka wrote: > > > > > Fixing __vmalloc code > > > is easy and it doesn't require cooperation with maintainers. > > > > But it is a hack against the intention of the scope api. > > It is not!

On Tue, 24 Apr 2018 12:33:01 -0400 (EDT) Mikulas Patocka <mpatocka at redhat.com> wrote: > > > On Tue, 24 Apr 2018, Michal Hocko wrote: > > > On Tue 24-04-18 11:30:40, Mikulas Patocka wrote: > > > > > > > > > On Tue, 24 Apr 2018, Michal Hocko wrote: > > > > > > > On Mon 23-04-18 20:25:15, Mikulas Patocka wrote: >

With 2.6.31-rc5 in a KVM guest using dm and virtio_blk, we see the following errors: end_request: I/O error, dev vda, sector 0 end_request: I/O error, dev vda, sector 0 The errors go away if dm stops submitting empty barriers, by reverting: commit 52b1fd5a27c625c78373e024bf570af3c9d44a79 Author: Mikulas Patocka <mpatocka at redhat.com> dm: send empty barriers to targets in

With 2.6.31-rc5 in a KVM guest using dm and virtio_blk, we see the following errors: end_request: I/O error, dev vda, sector 0 end_request: I/O error, dev vda, sector 0 The errors go away if dm stops submitting empty barriers, by reverting: commit 52b1fd5a27c625c78373e024bf570af3c9d44a79 Author: Mikulas Patocka <mpatocka at redhat.com> dm: send empty barriers to targets in

On Tue 24-04-18 13:28:49, Mikulas Patocka wrote: > > > On Tue, 24 Apr 2018, Michal Hocko wrote: > > > On Tue 24-04-18 13:00:11, Mikulas Patocka wrote: > > > > > > > > > On Tue, 24 Apr 2018, Michal Hocko wrote: > > > > > > > On Tue 24-04-18 11:50:30, Mikulas Patocka wrote: > > > > > > > > > >

commit d85b758f72b0 "virtio_net: fix support for small rings" was supposed to increase the buffer size for small rings but had an unintentional side effect of decreasing it for large rings. This seems to break some setups - it's not yet clear why, but increasing buffer size back to what it was before helps. Fixes: d85b758f72b0 "virtio_net: fix support for small rings"

commit d85b758f72b0 "virtio_net: fix support for small rings" was supposed to increase the buffer size for small rings but had an unintentional side effect of decreasing it for large rings. This seems to break some setups - it's not yet clear why, but increasing buffer size back to what it was before helps. Fixes: d85b758f72b0 "virtio_net: fix support for small rings"

On Mon 23-04-18 10:06:08, Mikulas Patocka wrote: > > > On Sat, 21 Apr 2018, Matthew Wilcox wrote: > > > On Fri, Apr 20, 2018 at 05:21:26PM -0400, Mikulas Patocka wrote: > > > On Fri, 20 Apr 2018, Matthew Wilcox wrote: > > > > On Fri, Apr 20, 2018 at 04:54:53PM -0400, Mikulas Patocka wrote: > > > > > On Fri, 20 Apr 2018, Michal Hocko wrote:

On Mon 23-04-18 10:06:08, Mikulas Patocka wrote: > > > On Sat, 21 Apr 2018, Matthew Wilcox wrote: > > > On Fri, Apr 20, 2018 at 05:21:26PM -0400, Mikulas Patocka wrote: > > > On Fri, 20 Apr 2018, Matthew Wilcox wrote: > > > > On Fri, Apr 20, 2018 at 04:54:53PM -0400, Mikulas Patocka wrote: > > > > > On Fri, 20 Apr 2018, Michal Hocko wrote:

On Thu 19-04-18 12:12:38, Mikulas Patocka wrote: [...] > From: Mikulas Patocka <mpatocka at redhat.com> > Subject: [PATCH] kvmalloc: always use vmalloc if CONFIG_DEBUG_VM > > The kvmalloc function tries to use kmalloc and falls back to vmalloc if > kmalloc fails. > > Unfortunatelly, some kernel code has bugs - it uses kvmalloc and then > uses DMA-API on the returned

On Thu 19-04-18 12:12:38, Mikulas Patocka wrote: [...] > From: Mikulas Patocka <mpatocka at redhat.com> > Subject: [PATCH] kvmalloc: always use vmalloc if CONFIG_DEBUG_VM > > The kvmalloc function tries to use kmalloc and falls back to vmalloc if > kmalloc fails. > > Unfortunatelly, some kernel code has bugs - it uses kvmalloc and then > uses DMA-API on the returned

On Tue 24-04-18 13:00:11, Mikulas Patocka wrote: > > > On Tue, 24 Apr 2018, Michal Hocko wrote: > > > On Tue 24-04-18 11:50:30, Mikulas Patocka wrote: > > > > > > > > > On Tue, 24 Apr 2018, Michal Hocko wrote: > > > > > > > On Mon 23-04-18 20:06:16, Mikulas Patocka wrote: > > > > [...] > > > > > @@

On Tue 24-04-18 13:00:11, Mikulas Patocka wrote: > > > On Tue, 24 Apr 2018, Michal Hocko wrote: > > > On Tue 24-04-18 11:50:30, Mikulas Patocka wrote: > > > > > > > > > On Tue, 24 Apr 2018, Michal Hocko wrote: > > > > > > > On Mon 23-04-18 20:06:16, Mikulas Patocka wrote: > > > > [...] > > > > > @@

commit d85b758f72b0 ("virtio_net: fix support for small rings") was supposed to increase the buffer size for small rings but had an unintentional side effect of decreasing it for large rings. This seems to break some setups - it's not yet clear why, but increasing buffer size back to what it was before helps. Fixes: d85b758f72b0 ("virtio_net: fix support for small rings")