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20241209101647epsmtip1b38007eedc5642adc4842acc46c53fa9~Pes44sYPt0637406374epsmtip1O; Mon, 9 Dec 2024 10:16:47 +0000 (GMT) From: "Dujeong.lee" To: "'Eric Dumazet'" , "'Youngmin Nam'" Cc: "'Jakub Kicinski'" , "'Neal Cardwell'" , , , , , , , , , , , , , , , , , , In-Reply-To: Subject: RE: [PATCH] tcp: check socket state before calling WARN_ON Date: Mon, 9 Dec 2024 19:16:47 +0900 Message-ID: <000001db4a23$746be360$5d43aa20$@samsung.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Mailer: Microsoft Outlook 16.0 Thread-Index: AQL4yZmsudMRkH1MkhPtbuC345sC9QKRMuYdAUIxOFgBsMn9rAIf5xWWAZwDXWsBNR7tnQJ0dudGAPMj/mwCPP60LAEh3GCHsBjSvFA= Content-Language: ko X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrCJsWRmVeSWpSXmKPExsWy7bCmqe6Ew2HpBo2PlCzebGK2uLZ3IrvF nPMtLBbrdrUyWTw99ojdYvIURoum/ZeYLQ5Mmclq8aj/BJvFtreHmSw+33rHbHF1N5C4sK2P 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9:58=E2=80=AFAM=20Youngmin=20Nam=20=0D=0A>=20wrote:=0D=0A>=20>=0D=0A>=20>=20On=20Fri,=20Dec=200= 6,=202024=20at=2009:35:32AM=20+0100,=20Eric=20Dumazet=20wrote:=0D=0A>=20>= =20>=20On=20Fri,=20Dec=206,=202024=20at=206:50=E2=80=AFAM=20Youngmin=20Nam= =20=0D=0A>=20wrote:=0D=0A>=20>=20>=20>=0D=0A>= =20>=20>=20>=20On=20Wed,=20Dec=2004,=202024=20at=2008:13:33AM=20+0100,=20Er= ic=20Dumazet=20wrote:=0D=0A>=20>=20>=20>=20>=20On=20Wed,=20Dec=204,=202024= =20at=204:35=E2=80=AFAM=20Youngmin=20Nam=0D=0A>=20=20wrote:=0D=0A>=20>=20>=20>=20>=20>=0D=0A>=20>=20>=20>=20>=20>=20On=20T= ue,=20Dec=2003,=202024=20at=2006:18:39PM=20-0800,=20Jakub=20Kicinski=20wrot= e:=0D=0A>=20>=20>=20>=20>=20>=20>=20On=20Tue,=203=20Dec=202024=2010:34:46= =20-0500=20Neal=20Cardwell=20wrote:=0D=0A>=20>=20>=20>=20>=20>=20>=20>=20>= =20I=20have=20not=20seen=20these=20warnings=20firing.=20Neal,=20have=20you= =20seen=0D=0A>=20this=20in=20the=20past=20?=0D=0A>=20>=20>=20>=20>=20>=20>= =20>=0D=0A>=20>=20>=20>=20>=20>=20>=20>=20I=20can't=20recall=20seeing=20the= se=20warnings=20over=20the=20past=205=20years=0D=0A>=20>=20>=20>=20>=20>=20= >=20>=20or=20so,=20and=20(from=20checking=20our=20monitoring)=20they=20don'= t=20seem=0D=0A>=20>=20>=20>=20>=20>=20>=20>=20to=20be=20firing=20in=20our= =20fleet=20recently.=0D=0A>=20>=20>=20>=20>=20>=20>=0D=0A>=20>=20>=20>=20>= =20>=20>=20FWIW=20I=20see=20this=20at=20Meta=20on=205.12=20kernels,=20but= =20nothing=20since.=0D=0A>=20>=20>=20>=20>=20>=20>=20Could=20be=20that=20on= e=20of=20our=20workloads=20is=20pinned=20to=205.12.=0D=0A>=20>=20>=20>=20>= =20>=20>=20Youngmin,=20what's=20the=20newest=20kernel=20you=20can=20repro= =20this=20on?=0D=0A>=20>=20>=20>=20>=20>=20>=0D=0A>=20>=20>=20>=20>=20>=20H= i=20Jakub.=0D=0A>=20>=20>=20>=20>=20>=20Thank=20you=20for=20taking=20an=20i= nterest=20in=20this=20issue.=0D=0A>=20>=20>=20>=20>=20>=0D=0A>=20>=20>=20>= =20>=20>=20We've=20seen=20this=20issue=20since=205.15=20kernel.=0D=0A>=20>= =20>=20>=20>=20>=20Now,=20we=20can=20see=20this=20on=206.6=20kernel=20which= =20is=20the=20newest=20kernel=20we=0D=0A>=20are=20running.=0D=0A>=20>=20>= =20>=20>=0D=0A>=20>=20>=20>=20>=20The=20fact=20that=20we=20are=20processing= =20ACK=20packets=20after=20the=20write=0D=0A>=20>=20>=20>=20>=20queue=20has= =20been=20purged=20would=20be=20a=20serious=20bug.=0D=0A>=20>=20>=20>=20>= =0D=0A>=20>=20>=20>=20>=20Thus=20the=20WARN()=20makes=20sense=20to=20us.=0D= =0A>=20>=20>=20>=20>=0D=0A>=20>=20>=20>=20>=20It=20would=20be=20easy=20to= =20build=20a=20packetdrill=20test.=20Please=20do=20so,=20then=0D=0A>=20>=20= >=20>=20>=20we=20can=20fix=20the=20root=20cause.=0D=0A>=20>=20>=20>=20>=0D= =0A>=20>=20>=20>=20>=20Thank=20you=20=21=0D=0A>=20>=20>=20>=20>=0D=0A>=20>= =20>=20>=0D=0A>=20>=20>=20>=20Hi=20Eric.=0D=0A>=20>=20>=20>=0D=0A>=20>=20>= =20>=20Unfortunately,=20we=20are=20not=20familiar=20with=20the=20Packetdril= l=20test.=0D=0A>=20>=20>=20>=20Refering=20to=20the=20official=20website=20o= 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=20=24=20adb=20shell=0D=0A>=20>=20>=20>=0D=0A>=20>=20>=20>=20And=20here=20i= s=20what=20I=20did=20on=20my=20device=0D=0A>=20>=20>=20>=0D=0A>=20>=20>=20>= =20erd9955:/data/packetdrill/gtests/net=20=23=20./packetdrill/run_all.py=20= -S=0D=0A>=20>=20>=20>=20-v=20-L=20-l=20tcp/=0D=0A>=20>=20>=20>=20/system/bi= n/sh:=20./packetdrill/run_all.py:=20No=20such=20file=20or=0D=0A>=20>=20>=20= >=20directory=0D=0A>=20>=20>=20>=0D=0A>=20>=20>=20>=20I'm=20not=20sure=20if= =20this=20procedure=20is=20correct.=0D=0A>=20>=20>=20>=20Could=20you=20help= =20us=20run=20the=20Packetdrill=20on=20an=20Android=20device=20?=0D=0A>=20>= =20>=0D=0A>=20>=20>=20packetdrill=20can=20run=20anywhere,=20for=20instance= =20on=20your=20laptop,=20no=20need=0D=0A>=20>=20>=20to=20compile=20/=20inst= all=20it=20on=20Android=0D=0A>=20>=20>=0D=0A>=20>=20>=20Then=20you=20can=20= run=20single=20test=20like=0D=0A>=20>=20>=0D=0A>=20>=20>=20=23=20packetdril= l=20gtests/net/tcp/sack/sack-route-refresh-ip-tos.pkt=0D=0A>=20>=20>=0D=0A>= =20>=0D=0A>=20>=20You=20mean..=20To=20test=20an=20Android=20device,=20we=20= need=20to=20run=20packetdrill=20on=0D=0A>=20laptop,=20right=20?=0D=0A>=20>= =0D=0A>=20>=20Laptop(run=20packetdrill=20script)=20<-----------------------= --->=20Android=0D=0A>=20>=20device=0D=0A>=20>=0D=0A>=20>=20By=20the=20way,= =20how=20can=20we=20test=20the=20Android=20device=20(DUT)=20from=20packetdr= ill=0D=0A>=20which=20is=20running=20on=20Laptop?=0D=0A>=20>=20I=20hope=20yo= u=20understand=20that=20I=20am=20aksing=20this=20question=20because=20we=20= are=20not=0D=0A>=20familiar=20with=20the=20packetdrill.=0D=0A>=20>=20Thanks= .=0D=0A>=20=0D=0A>=20packetdrill=20does=20not=20need=20to=20run=20on=20a=20= physical=20DUT,=20it=20uses=20a=20software=0D=0A>=20stack=20:=20TCP=20and= =20tun=20device.=0D=0A>=20=0D=0A>=20You=20have=20a=20kernel=20tree,=20compi= le=20it=20and=20run=20a=20VM,=20like=20virtme-ng=0D=0A>=20=0D=0A>=20vng=20-= bv=0D=0A>=20=0D=0A>=20We=20use=20this=20to=20run=20kernel=20selftests=20in= =20which=20we=20started=20adding=20packetdrill=0D=0A>=20tests=20(in=20recen= t=20kernel=20tree)=0D=0A>=20=0D=0A>=20./tools/testing/selftests/net/packetd= rill/tcp_slow_start_slow-start-ack-=0D=0A>=20per-4pkt.pkt=0D=0A>=20./tools/= testing/selftests/net/packetdrill/tcp_zerocopy_client.pkt=0D=0A>=20./tools/= testing/selftests/net/packetdrill/tcp_zerocopy_batch.pkt=0D=0A>=20./tools/t= esting/selftests/net/packetdrill/tcp_slow_start_slow-start-after-=0D=0A>=20= win-update.pkt=0D=0A>=20./tools/testing/selftests/net/packetdrill/tcp_slow_= start_slow-start-fq-=0D=0A>=20ack-per-2pkt.pkt=0D=0A>=20./tools/testing/sel= ftests/net/packetdrill/tcp_zerocopy_maxfrags.pkt=0D=0A>=20./tools/testing/s= elftests/net/packetdrill/tcp_inq_server.pkt=0D=0A>=20./tools/testing/selfte= sts/net/packetdrill/tcp_zerocopy_epoll_exclusive.pkt=0D=0A>=20./tools/testi= ng/selftests/net/packetdrill/tcp_zerocopy_basic.pkt=0D=0A>=20./tools/testin= g/selftests/net/packetdrill/tcp_zerocopy_small.pkt=0D=0A>=20./tools/testing= /selftests/net/packetdrill/tcp_slow_start_slow-start-app-=0D=0A>=20limited-= 9-packets-out.pkt=0D=0A>=20./tools/testing/selftests/net/packetdrill/tcp_sl= ow_start_slow-start-ack-=0D=0A>=20per-2pkt.pkt=0D=0A>=20./tools/testing/sel= ftests/net/packetdrill/tcp_zerocopy_epoll_oneshot.pkt=0D=0A>=20./tools/test= ing/selftests/net/packetdrill/tcp_zerocopy_fastopen-server.pkt=0D=0A>=20./t= ools/testing/selftests/net/packetdrill/tcp_inq_client.pkt=0D=0A>=20./tools/= testing/selftests/net/packetdrill/tcp_zerocopy_epoll_edge.pkt=0D=0A>=20./to= ols/testing/selftests/net/packetdrill/tcp_slow_start_slow-start-app-=0D=0A>= =20limited.pkt=0D=0A>=20./tools/testing/selftests/net/packetdrill/tcp_zeroc= opy_fastopen-client.pkt=0D=0A>=20./tools/testing/selftests/net/packetdrill/= tcp_zerocopy_closed.pkt=0D=0A>=20./tools/testing/selftests/net/packetdrill/= tcp_slow_start_slow-start-ack-=0D=0A>=20per-1pkt.pkt=0D=0A>=20./tools/testi= ng/selftests/net/packetdrill/tcp_slow_start_slow-start-after-=0D=0A>=20idle= .pkt=0D=0A>=20./tools/testing/selftests/net/packetdrill/tcp_slow_start_slow= -start-ack-=0D=0A>=20per-2pkt-send-5pkt.pkt=0D=0A>=20./tools/testing/selfte= sts/net/packetdrill/tcp_slow_start_slow-start-ack-=0D=0A>=20per-2pkt-send-6= pkt.pkt=0D=0A>=20./tools/testing/selftests/net/packetdrill/tcp_md5_md5-only= -on-client-=0D=0A>=20ack.pkt=0D=0A>=20./tools/testing/selftests/net/netfilt= er/packetdrill/conntrack_synack_old.p=0D=0A>=20kt=0D=0A>=20./tools/testing/= selftests/net/netfilter/packetdrill/conntrack_syn_challeng=0D=0A>=20e_ack.p= kt=0D=0A>=20./tools/testing/selftests/net/netfilter/packetdrill/conntrack_i= nexact_rst.=0D=0A>=20pkt=0D=0A>=20./tools/testing/selftests/net/netfilter/p= acketdrill/conntrack_synack_reuse=0D=0A>=20.pkt=0D=0A>=20./tools/testing/se= lftests/net/netfilter/packetdrill/conntrack_rst_invalid.=0D=0A>=20pkt=0D=0A= >=20./tools/testing/selftests/net/netfilter/packetdrill/conntrack_ack_loss_= sta=0D=0A>=20ll.pkt=0D=0A=0D=0AThanks=20for=20all=20the=20details=20on=20pa= cketdrill=20and=20we=20are=20also=20exploring=20USENIX=202013=20material.= =0D=0AI=20have=20one=20question.=20The=20issue=20happens=20when=20DUT=20rec= eives=20TCP=20ack=20with=20large=20delay=20from=20network,=20e.g.,=2028seco= nds=20since=20last=20Tx.=20Is=20packetdrill=20able=20to=20emulate=20this=20= network=20delay=20(or=20congestion)=20in=20script=20level?=0D=0A=0D=0A