| Message ID | 20100904203429.GA4891@del.dom.local |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
Le samedi 04 septembre 2010 à 22:34 +0200, Jarek Poplawski a écrit : > Hi again, > > Just had a second look, and unless I miss something... > > Plamen, could you test this patch, too? (Without removing the previous > one.) > > Thanks, > Jarek P. > > -------------------> > > [PATCH] gro: Re-fix different skb headrooms > > The patch: "gro: fix different skb headrooms" in its part: > "2) allocate a minimal skb for head of frag_list" is buggy. The copied > skb has p->data set at the ip header at the moment, and skb_gro_offset > is the length of ip + tcp headers. So, after the change the length of > mac header is skipped. Later skb_set_mac_header() sets it into the > NET_SKB_PAD area (if it's long enough) and ip header is misaligned at > NET_SKB_PAD + NET_IP_ALIGN offset. There is no reason to assume the > original skb was wrongly allocated, so let's copy it as it was. > > bugzilla : https://bugzilla.kernel.org/show_bug.cgi?id=16626 > fixes commit: 3d3be4333fdf6faa080947b331a6a19bce1a4f57 > > Reported-by: Plamen Petrov <pvp-lsts@fs.uni-ruse.bg> > Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> > CC: Eric Dumazet <eric.dumazet@gmail.com> > --- > > diff --git a/net/core/skbuff.c b/net/core/skbuff.c > index 26396ff..c83b421 100644 > --- a/net/core/skbuff.c > +++ b/net/core/skbuff.c > @@ -2706,7 +2706,7 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb) > } else if (skb_gro_len(p) != pinfo->gso_size) > return -E2BIG; > > - headroom = NET_SKB_PAD + NET_IP_ALIGN; > + headroom = skb_headroom(p); > nskb = alloc_skb(headroom + skb_gro_offset(p), GFP_ATOMIC); > if (unlikely(!nskb)) > return -ENOMEM; You are right, thanks for reviewing this patch again :) By the way, NET_IP_ALIGN is now 0 on x86, so technically speaking, your patch un-aligns IP header on x86, but thats OK, since other arches might want it being aligned, while x86 doesnt care. Acked-by: Eric Dumazet <eric.dumazet@gmail.com> -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
На 05.9.2010 г. 10:49, Eric Dumazet написа: > Le samedi 04 septembre 2010 à 22:34 +0200, Jarek Poplawski a écrit : > >> Hi again, >> >> Just had a second look, and unless I miss something... >> >> Plamen, could you test this patch, too? (Without removing the previous >> one.) >> >> Thanks, >> Jarek P. >> >> -------------------> >> >> [PATCH] gro: Re-fix different skb headrooms >> >> The patch: "gro: fix different skb headrooms" in its part: >> "2) allocate a minimal skb for head of frag_list" is buggy. The copied >> skb has p->data set at the ip header at the moment, and skb_gro_offset >> is the length of ip + tcp headers. So, after the change the length of >> mac header is skipped. Later skb_set_mac_header() sets it into the >> NET_SKB_PAD area (if it's long enough) and ip header is misaligned at >> NET_SKB_PAD + NET_IP_ALIGN offset. There is no reason to assume the >> original skb was wrongly allocated, so let's copy it as it was. >> >> bugzilla : https://bugzilla.kernel.org/show_bug.cgi?id=16626 >> fixes commit: 3d3be4333fdf6faa080947b331a6a19bce1a4f57 >> >> Reported-by: Plamen Petrov<pvp-lsts@fs.uni-ruse.bg> >> Signed-off-by: Jarek Poplawski<jarkao2@gmail.com> >> CC: Eric Dumazet<eric.dumazet@gmail.com> >> --- >> >> diff --git a/net/core/skbuff.c b/net/core/skbuff.c >> index 26396ff..c83b421 100644 >> --- a/net/core/skbuff.c >> +++ b/net/core/skbuff.c >> @@ -2706,7 +2706,7 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb) >> } else if (skb_gro_len(p) != pinfo->gso_size) >> return -E2BIG; >> >> - headroom = NET_SKB_PAD + NET_IP_ALIGN; >> + headroom = skb_headroom(p); >> nskb = alloc_skb(headroom + skb_gro_offset(p), GFP_ATOMIC); >> if (unlikely(!nskb)) >> return -ENOMEM; > > You are right, thanks for reviewing this patch again :) > > By the way, NET_IP_ALIGN is now 0 on x86, so technically speaking, your > patch un-aligns IP header on x86, but thats OK, since other arches might > want it being aligned, while x86 doesnt care. > > Acked-by: Eric Dumazet<eric.dumazet@gmail.com> > > > Well, now that I'm back at work, I'm glad to report that I tested both variants of the patch, and as Eric points out - it works both ways. So, which ever fits you guys better. Thanks a lot! -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Sep 08, 2010 at 07:57:31AM +0300, Plamen Petrov wrote: > ???? 05.9.2010 ??. 10:49, Eric Dumazet ????????????: >> Le samedi 04 septembre 2010 ?? 22:34 +0200, Jarek Poplawski a écrit : >> >>> Hi again, >>> >>> Just had a second look, and unless I miss something... >>> >>> Plamen, could you test this patch, too? (Without removing the previous >>> one.) >>> >>> Thanks, >>> Jarek P. >>> >>> -------------------> >>> >>> [PATCH] gro: Re-fix different skb headrooms >>> >>> The patch: "gro: fix different skb headrooms" in its part: >>> "2) allocate a minimal skb for head of frag_list" is buggy. The copied >>> skb has p->data set at the ip header at the moment, and skb_gro_offset >>> is the length of ip + tcp headers. So, after the change the length of >>> mac header is skipped. Later skb_set_mac_header() sets it into the >>> NET_SKB_PAD area (if it's long enough) and ip header is misaligned at >>> NET_SKB_PAD + NET_IP_ALIGN offset. There is no reason to assume the >>> original skb was wrongly allocated, so let's copy it as it was. >>> >>> bugzilla : https://bugzilla.kernel.org/show_bug.cgi?id=16626 >>> fixes commit: 3d3be4333fdf6faa080947b331a6a19bce1a4f57 >>> >>> Reported-by: Plamen Petrov<pvp-lsts@fs.uni-ruse.bg> >>> Signed-off-by: Jarek Poplawski<jarkao2@gmail.com> >>> CC: Eric Dumazet<eric.dumazet@gmail.com> >>> --- >>> >>> diff --git a/net/core/skbuff.c b/net/core/skbuff.c >>> index 26396ff..c83b421 100644 >>> --- a/net/core/skbuff.c >>> +++ b/net/core/skbuff.c >>> @@ -2706,7 +2706,7 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb) >>> } else if (skb_gro_len(p) != pinfo->gso_size) >>> return -E2BIG; >>> >>> - headroom = NET_SKB_PAD + NET_IP_ALIGN; >>> + headroom = skb_headroom(p); >>> nskb = alloc_skb(headroom + skb_gro_offset(p), GFP_ATOMIC); >>> if (unlikely(!nskb)) >>> return -ENOMEM; >> >> You are right, thanks for reviewing this patch again :) >> >> By the way, NET_IP_ALIGN is now 0 on x86, so technically speaking, your >> patch un-aligns IP header on x86, but thats OK, since other arches might >> want it being aligned, while x86 doesnt care. >> >> Acked-by: Eric Dumazet<eric.dumazet@gmail.com> >> >> >> > > Well, now that I'm back at work, I'm glad to report > that I tested both variants of the patch, and as Eric > points out - it works both ways. > > So, which ever fits you guys better. We need both of them. I hope David could add this too: Tested-by: Plamen Petrov <pvp-lsts@fs.uni-ruse.bg> Thanks a lot everybody! Jarek P. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Jarek Poplawski <jarkao2@gmail.com> Date: Wed, 8 Sep 2010 06:20:04 +0000 > We need both of them. I hope David could add this too: > > Tested-by: Plamen Petrov <pvp-lsts@fs.uni-ruse.bg> Done, and applied, thanks :-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wednesday, September 08, 2010, David Miller wrote: > From: Jarek Poplawski <jarkao2@gmail.com> > Date: Wed, 8 Sep 2010 06:20:04 +0000 > > > We need both of them. I hope David could add this too: > > > > Tested-by: Plamen Petrov <pvp-lsts@fs.uni-ruse.bg> > > Done, and applied, thanks :-) Please kindly let me know when Linus gets them, so that I can close the bug. Rafael -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
На 08.9.2010 г. 23:21, Rafael J. Wysocki написа: > On Wednesday, September 08, 2010, David Miller wrote: >> From: Jarek Poplawski<jarkao2@gmail.com> >> Date: Wed, 8 Sep 2010 06:20:04 +0000 >> >>> We need both of them. I hope David could add this too: >>> >>> Tested-by: Plamen Petrov<pvp-lsts@fs.uni-ruse.bg> >> >> Done, and applied, thanks :-) > > Please kindly let me know when Linus gets them, so that I can close the bug. > > Rafael Now that both commits that fix my problems are in Linus' tree, the bug can be closed, but these fixes should go in 2.6.35.y, too. So, CCing -stable. Fix 1: > commit 3d3be4333fdf6faa080947b331a6a19bce1a4f57 > > gro: fix different skb headrooms > > Packets entering GRO might have different headrooms, even for a given > flow (because of implementation details in drivers, like copybreak). > We cant force drivers to deliver packets with a fixed headroom. > > 1) fix skb_segment() > > skb_segment() makes the false assumption headrooms of fragments are same > than the head. When CHECKSUM_PARTIAL is used, this can give csum_start > errors, and crash later in skb_copy_and_csum_dev() > > 2) allocate a minimal skb for head of frag_list > > skb_gro_receive() uses netdev_alloc_skb(headroom + skb_gro_offset(p)) to > allocate a fresh skb. This adds NET_SKB_PAD to a padding already > provided by netdevice, depending on various things, like copybreak. > > Use alloc_skb() to allocate an exact padding, to reduce cache line > needs: > NET_SKB_PAD + NET_IP_ALIGN > > bugzilla : https://bugzilla.kernel.org/show_bug.cgi?id=16626 > > Many thanks to Plamen Petrov, testing many debugging patches ! > With help of Jarek Poplawski. > > Reported-by: Plamen Petrov <pvp-lsts@fs.uni-ruse.bg> > Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> > CC: Jarek Poplawski <jarkao2@gmail.com> > Signed-off-by: David S. Miller <davem@davemloft.net> Fix 2: > commit 64289c8e6851bca0e589e064c9a5c9fbd6ae5dd4 > > gro: Re-fix different skb headrooms > > The patch: "gro: fix different skb headrooms" in its part: > "2) allocate a minimal skb for head of frag_list" is buggy. The copied > skb has p->data set at the ip header at the moment, and skb_gro_offset > is the length of ip + tcp headers. So, after the change the length of > mac header is skipped. Later skb_set_mac_header() sets it into the > NET_SKB_PAD area (if it's long enough) and ip header is misaligned at > NET_SKB_PAD + NET_IP_ALIGN offset. There is no reason to assume the > original skb was wrongly allocated, so let's copy it as it was. > > bugzilla : https://bugzilla.kernel.org/show_bug.cgi?id=16626 > fixes commit: 3d3be4333fdf6faa080947b331a6a19bce1a4f57 > > Reported-by: Plamen Petrov <pvp-lsts@fs.uni-ruse.bg> > Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> > CC: Eric Dumazet <eric.dumazet@gmail.com> > Acked-by: Eric Dumazet <eric.dumazet@gmail.com> > Tested-by: Plamen Petrov <pvp-lsts@fs.uni-ruse.bg> > Signed-off-by: David S. Miller <davem@davemloft.net> Thanks, Plamen -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Plamen Petrov <pvp-lsts@fs.uni-ruse.bg> Date: Sun, 12 Sep 2010 09:55:19 +0300 > Now that both commits that fix my problems are in Linus' tree, the > bug can be closed, but these fixes should go in 2.6.35.y, too. > So, CCing -stable. You don't need to do this, I will submit whatever is appropriate for networking to -stable as needed. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sunday, September 12, 2010, Plamen Petrov wrote: > На 08.9.2010 г. 23:21, Rafael J. Wysocki написа: > > On Wednesday, September 08, 2010, David Miller wrote: > >> From: Jarek Poplawski<jarkao2@gmail.com> > >> Date: Wed, 8 Sep 2010 06:20:04 +0000 > >> > >>> We need both of them. I hope David could add this too: > >>> > >>> Tested-by: Plamen Petrov<pvp-lsts@fs.uni-ruse.bg> > >> > >> Done, and applied, thanks :-) > > > > Please kindly let me know when Linus gets them, so that I can close the bug. > > > > Rafael > > Now that both commits that fix my problems are in Linus' tree, the > bug can be closed, but these fixes should go in 2.6.35.y, too. > So, CCing -stable. Thanks, bug closed. Rafael -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
На 12.9.2010 г. 18:55, David Miller написа: > From: Plamen Petrov<pvp-lsts@fs.uni-ruse.bg> > Date: Sun, 12 Sep 2010 09:55:19 +0300 > >> Now that both commits that fix my problems are in Linus' tree, the >> bug can be closed, but these fixes should go in 2.6.35.y, too. >> So, CCing -stable. > > You don't need to do this, I will submit whatever is appropriate for > networking to -stable as needed. Sorry! I didn't know it will be taken care of. Thanks! Plamen -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 26396ff..c83b421 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2706,7 +2706,7 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb) } else if (skb_gro_len(p) != pinfo->gso_size) return -E2BIG; - headroom = NET_SKB_PAD + NET_IP_ALIGN; + headroom = skb_headroom(p); nskb = alloc_skb(headroom + skb_gro_offset(p), GFP_ATOMIC); if (unlikely(!nskb)) return -ENOMEM;