> -----Original Message----- > From: Marc Zyngier [mailto:marc.zyng...@arm.com] > Sent: Tuesday, December 15, 2015 3:50 PM > To: Bhushan Bharat-R65777 <bharat.bhus...@freescale.com>; > kvm...@lists.cs.columbia.edu; kvm@vger.kernel.org; linux-arm- > ker...@lists.infradead.org; linux-ker...@vger.kernel.org > Subject: Re: ARM64/KVM: Bad page state in process iperf > > On 15/12/15 09:53, Bhushan Bharat wrote: > > Hi Mark, > > > >> -----Original Message----- > >> From: Marc Zyngier [mailto:marc.zyng...@arm.com] > >> Sent: Tuesday, December 15, 2015 3:05 PM > >> To: Bhushan Bharat-R65777 <bharat.bhus...@freescale.com>; > >> kvm...@lists.cs.columbia.edu; kvm@vger.kernel.org; linux-arm- > >> ker...@lists.infradead.org; linux-ker...@vger.kernel.org > >> Subject: Re: ARM64/KVM: Bad page state in process iperf > >> > >> On 15/12/15 03:46, Bhushan Bharat wrote: > >>> > >>> Hi All, > >>> > >>> I am running "iperf" in KVM guest on ARM64 machine and observing > >>> below > >> crash. > >>> > >>> ============================= > >>> $iperf -c 3.3.3.3 -P 4 -t 0 -i 5 -w 90k > >>> ------------------------------------------------------------ > >>> Client connecting to 3.3.3.3, TCP port 5001 TCP window size: 180 > >>> KByte (WARNING: requested 90.0 KByte) > >>> ------------------------------------------------------------ > >>> [ 3] local 3.3.3.1 port 51131 connected with 3.3.3.3 port 5001 [ > >>> 6] local 3.3.3.1 port 51134 connected with 3.3.3.3 port 5001 [ 5] > >>> local > >>> 3.3.3.1 port 51133 connected with 3.3.3.3 port 5001 [ 4] local > >>> 3.3.3.1 port 51132 connected with 3.3.3.3 port 5001 > >>> [ 53.088567] random: nonblocking pool is initialized > >>> [ ID] Interval Transfer Bandwidth > >>> [ 3] 0.0- 5.0 sec 638 MBytes 1.07 Gbits/sec > >>> [ 4] 35.0-40.0 sec 1.66 GBytes 2.85 Gbits/sec [ 5] 40.0-45.0 sec > >>> 1.11 GBytes 1.90 Gbits/sec [ 4] 40.0-45.0 sec 1.16 GBytes 1.99 > >>> Gbits/sec > >>> [ 98.895207] BUG: Bad page state in process iperf pfn:0a584 > >>> [ 98.896164] page:ffff780000296100 count:-1 mapcount:0 mapping: > >> (null) index:0x0 > >>> [ 98.897436] flags: 0x0() > >>> [ 98.897885] page dumped because: nonzero _count > >>> [ 98.898640] Modules linked in: > >>> [ 98.899178] CPU: 0 PID: 1639 Comm: iperf Not tainted 4.1.8-00461- > >> ge5431ad #141 > >>> [ 98.900302] Hardware name: linux,dummy-virt (DT) > >>> [ 98.901014] Call trace: > >>> [ 98.901406] [<ffff800000096cac>] dump_backtrace+0x0/0x12c > >>> [ 98.902522] [<ffff800000096de8>] show_stack+0x10/0x1c > >>> [ 98.903441] [<ffff800000678dc8>] dump_stack+0x8c/0xdc > >>> [ 98.904202] [<ffff800000145480>] bad_page+0xc4/0x114 > >>> [ 98.904945] [<ffff8000001487a4>] > get_page_from_freelist+0x590/0x63c > >>> [ 98.905871] [<ffff80000014893c>] > __alloc_pages_nodemask+0xec/0x794 > >>> [ 98.906791] [<ffff80000059fc80>] skb_page_frag_refill+0x70/0xa8 > >>> [ 98.907678] [<ffff80000059fcd8>] sk_page_frag_refill+0x20/0xd0 > >>> [ 98.908550] [<ffff8000005edc04>] tcp_sendmsg+0x1f8/0x9a8 > >>> [ 98.909368] [<ffff80000061419c>] inet_sendmsg+0x5c/0xd0 > >>> [ 98.910178] [<ffff80000059bb44>] sock_sendmsg+0x14/0x58 > >>> [ 98.911027] [<ffff80000059bbec>] sock_write_iter+0x64/0xbc > >>> [ 98.912119] [<ffff80000019b5b8>] __vfs_write+0xac/0x10c > >>> [ 98.913126] [<ffff80000019bcb8>] vfs_write+0x90/0x1a0 > >>> [ 98.913963] [<ffff80000019c53c>] SyS_write+0x40/0xa0 > >> > >> This looks quite bad, but I don't see anything here that links it to > >> KVM (apart from being a guest). Do you have any indication that this > >> is due to KVM misbehaving? > > > > I never observed this issue in host Linux but observed this issue always in > guest Linux. This issue does not comes immediately after I run "iperf" but > after some time. > > > >> I'd appreciate a few more details. > > > > We have a networking hardware and we are directly assigning the h/w to > guest. When using the same networking hardware in host it always works as > expected (tried 100s of times). > > Also this issue is not observed when we have only one vCPU in guest but > seen when we have SMP guest. > > Can you reproduce the same issue without VFIO (using virtio, for example)?
With virtio I have not observed this issue. > Is that platform VFIO? or PCI? It is not vfio-pci and vfio-platform. It is vfio-fls-mc (some Freescale new hardware), similar to the lines of vfio-platform uses same set of VFIO APIs used by vfio-pci/platform. Do you think this can be some h/w specific issue. Thanks -Bharat > > Thanks, > > M. > -- > Jazz is not dead. It just smells funny... -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
