From dffa1a269aa5666e0472e053336b021f9b794203 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 23 Nov 2021 13:33:40 +0100 Subject: [PATCH] 5.4-stable patches added patches: batman-adv-consider-fragmentation-for-needed_headroom.patch batman-adv-don-t-always-reallocate-the-fragmentation-skb-head.patch batman-adv-reserve-needed_-room-for-fragments.patch perf-core-avoid-put_page-when-gup-fails.patch --- ...er-fragmentation-for-needed_headroom.patch | 41 +++++++++ ...eallocate-the-fragmentation-skb-head.patch | 52 +++++++++++ ...v-reserve-needed_-room-for-fragments.patch | 92 +++++++++++++++++++ ...f-core-avoid-put_page-when-gup-fails.patch | 61 ++++++++++++ queue-5.4/series | 4 + 5 files changed, 250 insertions(+) create mode 100644 queue-5.4/batman-adv-consider-fragmentation-for-needed_headroom.patch create mode 100644 queue-5.4/batman-adv-don-t-always-reallocate-the-fragmentation-skb-head.patch create mode 100644 queue-5.4/batman-adv-reserve-needed_-room-for-fragments.patch create mode 100644 queue-5.4/perf-core-avoid-put_page-when-gup-fails.patch diff --git a/queue-5.4/batman-adv-consider-fragmentation-for-needed_headroom.patch b/queue-5.4/batman-adv-consider-fragmentation-for-needed_headroom.patch new file mode 100644 index 00000000000..f19bd44b15f --- /dev/null +++ b/queue-5.4/batman-adv-consider-fragmentation-for-needed_headroom.patch @@ -0,0 +1,41 @@ +From foo@baz Tue Nov 23 01:32:30 PM CET 2021 +From: Sven Eckelmann +Date: Sat, 20 Nov 2021 13:40:51 +0100 +Subject: batman-adv: Consider fragmentation for needed_headroom +To: stable@vger.kernel.org +Cc: b.a.t.m.a.n@lists.open-mesh.org, "Sven Eckelmann" , "Linus Lüssing" , "Simon Wunderlich" +Message-ID: <20211120124053.261156-2-sven@narfation.org> + +From: Sven Eckelmann + +commit 4ca23e2c2074465bff55ea14221175fecdf63c5f upstream. + +If a batman-adv packets has to be fragmented, then the original batman-adv +packet header is not stripped away. Instead, only a new header is added in +front of the packet after it was split. + +This size must be considered to avoid cost intensive reallocations during +the transmission through the various device layers. + +Fixes: 7bca68c7844b ("batman-adv: Add lower layer needed_(head|tail)room to own ones") +Reported-by: Linus Lüssing +Signed-off-by: Sven Eckelmann +Signed-off-by: Simon Wunderlich +Signed-off-by: Sven Eckelmann +Signed-off-by: Greg Kroah-Hartman +--- + net/batman-adv/hard-interface.c | 3 +++ + 1 file changed, 3 insertions(+) + +--- a/net/batman-adv/hard-interface.c ++++ b/net/batman-adv/hard-interface.c +@@ -554,6 +554,9 @@ static void batadv_hardif_recalc_extra_s + needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN); + needed_headroom += batadv_max_header_len(); + ++ /* fragmentation headers don't strip the unicast/... header */ ++ needed_headroom += sizeof(struct batadv_frag_packet); ++ + soft_iface->needed_headroom = needed_headroom; + soft_iface->needed_tailroom = lower_tailroom; + } diff --git a/queue-5.4/batman-adv-don-t-always-reallocate-the-fragmentation-skb-head.patch b/queue-5.4/batman-adv-don-t-always-reallocate-the-fragmentation-skb-head.patch new file mode 100644 index 00000000000..ca4a232cfcb --- /dev/null +++ b/queue-5.4/batman-adv-don-t-always-reallocate-the-fragmentation-skb-head.patch @@ -0,0 +1,52 @@ +From foo@baz Tue Nov 23 01:32:30 PM CET 2021 +From: Sven Eckelmann +Date: Sat, 20 Nov 2021 13:40:53 +0100 +Subject: batman-adv: Don't always reallocate the fragmentation skb head +To: stable@vger.kernel.org +Cc: b.a.t.m.a.n@lists.open-mesh.org, Sven Eckelmann , Simon Wunderlich +Message-ID: <20211120124053.261156-4-sven@narfation.org> + +From: Sven Eckelmann + +commit 992b03b88e36254e26e9a4977ab948683e21bd9f upstream. + +When a packet is fragmented by batman-adv, the original batman-adv header +is not modified. Only a new fragmentation is inserted between the original +one and the ethernet header. The code must therefore make sure that it has +a writable region of this size in the skbuff head. + +But it is not useful to always reallocate the skbuff by this size even when +there would be more than enough headroom still in the skb. The reallocation +is just to costly during in this codepath. + +Fixes: ee75ed88879a ("batman-adv: Fragment and send skbs larger than mtu") +Signed-off-by: Sven Eckelmann +Signed-off-by: Simon Wunderlich +Signed-off-by: Sven Eckelmann +Signed-off-by: Greg Kroah-Hartman +--- + net/batman-adv/fragmentation.c | 11 ++++++----- + 1 file changed, 6 insertions(+), 5 deletions(-) + +--- a/net/batman-adv/fragmentation.c ++++ b/net/batman-adv/fragmentation.c +@@ -527,13 +527,14 @@ int batadv_frag_send_packet(struct sk_bu + frag_header.no++; + } + +- /* Make room for the fragment header. */ +- if (batadv_skb_head_push(skb, header_size) < 0 || +- pskb_expand_head(skb, header_size + ETH_HLEN, 0, GFP_ATOMIC) < 0) { +- ret = -ENOMEM; ++ /* make sure that there is at least enough head for the fragmentation ++ * and ethernet headers ++ */ ++ ret = skb_cow_head(skb, ETH_HLEN + header_size); ++ if (ret < 0) + goto put_primary_if; +- } + ++ skb_push(skb, header_size); + memcpy(skb->data, &frag_header, header_size); + + /* Send the last fragment */ diff --git a/queue-5.4/batman-adv-reserve-needed_-room-for-fragments.patch b/queue-5.4/batman-adv-reserve-needed_-room-for-fragments.patch new file mode 100644 index 00000000000..5054c9f84cc --- /dev/null +++ b/queue-5.4/batman-adv-reserve-needed_-room-for-fragments.patch @@ -0,0 +1,92 @@ +From foo@baz Tue Nov 23 01:32:30 PM CET 2021 +From: Sven Eckelmann +Date: Sat, 20 Nov 2021 13:40:52 +0100 +Subject: batman-adv: Reserve needed_*room for fragments +To: stable@vger.kernel.org +Cc: b.a.t.m.a.n@lists.open-mesh.org, Sven Eckelmann , Simon Wunderlich +Message-ID: <20211120124053.261156-3-sven@narfation.org> + +From: Sven Eckelmann + +commit c5cbfc87558168ef4c3c27ce36eba6b83391db19 upstream. + +The batadv net_device is trying to propagate the needed_headroom and +needed_tailroom from the lower devices. This is needed to avoid cost +intensive reallocations using pskb_expand_head during the transmission. + +But the fragmentation code split the skb's without adding extra room at the +end/beginning of the various fragments. This reduced the performance of +transmissions over complex scenarios (batadv on vxlan on wireguard) because +the lower devices had to perform the reallocations at least once. + +Fixes: ee75ed88879a ("batman-adv: Fragment and send skbs larger than mtu") +Signed-off-by: Sven Eckelmann +Signed-off-by: Simon Wunderlich +Signed-off-by: Sven Eckelmann +Signed-off-by: Greg Kroah-Hartman +--- + net/batman-adv/fragmentation.c | 15 ++++++++++----- + 1 file changed, 10 insertions(+), 5 deletions(-) + +--- a/net/batman-adv/fragmentation.c ++++ b/net/batman-adv/fragmentation.c +@@ -391,6 +391,7 @@ out: + + /** + * batadv_frag_create() - create a fragment from skb ++ * @net_dev: outgoing device for fragment + * @skb: skb to create fragment from + * @frag_head: header to use in new fragment + * @fragment_size: size of new fragment +@@ -401,22 +402,25 @@ out: + * + * Return: the new fragment, NULL on error. + */ +-static struct sk_buff *batadv_frag_create(struct sk_buff *skb, ++static struct sk_buff *batadv_frag_create(struct net_device *net_dev, ++ struct sk_buff *skb, + struct batadv_frag_packet *frag_head, + unsigned int fragment_size) + { ++ unsigned int ll_reserved = LL_RESERVED_SPACE(net_dev); ++ unsigned int tailroom = net_dev->needed_tailroom; + struct sk_buff *skb_fragment; + unsigned int header_size = sizeof(*frag_head); + unsigned int mtu = fragment_size + header_size; + +- skb_fragment = netdev_alloc_skb(NULL, mtu + ETH_HLEN); ++ skb_fragment = dev_alloc_skb(ll_reserved + mtu + tailroom); + if (!skb_fragment) + goto err; + + skb_fragment->priority = skb->priority; + + /* Eat the last mtu-bytes of the skb */ +- skb_reserve(skb_fragment, header_size + ETH_HLEN); ++ skb_reserve(skb_fragment, ll_reserved + header_size); + skb_split(skb, skb_fragment, skb->len - fragment_size); + + /* Add the header */ +@@ -439,11 +443,12 @@ int batadv_frag_send_packet(struct sk_bu + struct batadv_orig_node *orig_node, + struct batadv_neigh_node *neigh_node) + { ++ struct net_device *net_dev = neigh_node->if_incoming->net_dev; + struct batadv_priv *bat_priv; + struct batadv_hard_iface *primary_if = NULL; + struct batadv_frag_packet frag_header; + struct sk_buff *skb_fragment; +- unsigned int mtu = neigh_node->if_incoming->net_dev->mtu; ++ unsigned int mtu = net_dev->mtu; + unsigned int header_size = sizeof(frag_header); + unsigned int max_fragment_size, num_fragments; + int ret; +@@ -503,7 +508,7 @@ int batadv_frag_send_packet(struct sk_bu + goto put_primary_if; + } + +- skb_fragment = batadv_frag_create(skb, &frag_header, ++ skb_fragment = batadv_frag_create(net_dev, skb, &frag_header, + max_fragment_size); + if (!skb_fragment) { + ret = -ENOMEM; diff --git a/queue-5.4/perf-core-avoid-put_page-when-gup-fails.patch b/queue-5.4/perf-core-avoid-put_page-when-gup-fails.patch new file mode 100644 index 00000000000..38035c28f47 --- /dev/null +++ b/queue-5.4/perf-core-avoid-put_page-when-gup-fails.patch @@ -0,0 +1,61 @@ +From 4716023a8f6a0f4a28047f14dd7ebdc319606b84 Mon Sep 17 00:00:00 2001 +From: Greg Thelen +Date: Wed, 10 Nov 2021 18:18:14 -0800 +Subject: perf/core: Avoid put_page() when GUP fails + +From: Greg Thelen + +commit 4716023a8f6a0f4a28047f14dd7ebdc319606b84 upstream. + +PEBS PERF_SAMPLE_PHYS_ADDR events use perf_virt_to_phys() to convert PMU +sampled virtual addresses to physical using get_user_page_fast_only() +and page_to_phys(). + +Some get_user_page_fast_only() error cases return false, indicating no +page reference, but still initialize the output page pointer with an +unreferenced page. In these error cases perf_virt_to_phys() calls +put_page(). This causes page reference count underflow, which can lead +to unintentional page sharing. + +Fix perf_virt_to_phys() to only put_page() if get_user_page_fast_only() +returns a referenced page. + +Fixes: fc7ce9c74c3ad ("perf/core, x86: Add PERF_SAMPLE_PHYS_ADDR") +Signed-off-by: Greg Thelen +Signed-off-by: Peter Zijlstra (Intel) +Link: https://lkml.kernel.org/r/20211111021814.757086-1-gthelen@google.com +Signed-off-by: Greg Kroah-Hartman +--- + kernel/events/core.c | 10 +++++----- + 1 file changed, 5 insertions(+), 5 deletions(-) + +--- a/kernel/events/core.c ++++ b/kernel/events/core.c +@@ -6536,7 +6536,6 @@ void perf_output_sample(struct perf_outp + static u64 perf_virt_to_phys(u64 virt) + { + u64 phys_addr = 0; +- struct page *p = NULL; + + if (!virt) + return 0; +@@ -6555,14 +6554,15 @@ static u64 perf_virt_to_phys(u64 virt) + * If failed, leave phys_addr as 0. + */ + if (current->mm != NULL) { ++ struct page *p; ++ + pagefault_disable(); +- if (__get_user_pages_fast(virt, 1, 0, &p) == 1) ++ if (__get_user_pages_fast(virt, 1, 0, &p) == 1) { + phys_addr = page_to_phys(p) + virt % PAGE_SIZE; ++ put_page(p); ++ } + pagefault_enable(); + } +- +- if (p) +- put_page(p); + } + + return phys_addr; diff --git a/queue-5.4/series b/queue-5.4/series index cf0a488e59d..c3d4a6f0a40 100644 --- a/queue-5.4/series +++ b/queue-5.4/series @@ -88,3 +88,7 @@ drm-nouveau-use-drm_dev_unplug-during-device-removal.patch drm-i915-dp-ensure-sink-rate-values-are-always-valid.patch drm-amdgpu-fix-set-scaling-mode-full-full-aspect-center-not-works-on-vga-and-dvi-connectors.patch revert-net-mvpp2-disable-force-link-up-during-port-init-procedure.patch +perf-core-avoid-put_page-when-gup-fails.patch +batman-adv-consider-fragmentation-for-needed_headroom.patch +batman-adv-reserve-needed_-room-for-fragments.patch +batman-adv-don-t-always-reallocate-the-fragmentation-skb-head.patch -- 2.47.2