tools: Factor Clang, LLC and LLVM utils definitions #682
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When dealing with BPF/BTF/pahole and DWARF v5 I wanted to build bpftool. While looking into the source code I found duplicate assignments in misc tools for the LLVM eco system, e.g. clang and llvm-objcopy. Move the Clang, LLC and/or LLVM utils definitions to tools/scripts/Makefile.include file and add missing includes where needed. Honestly, I was inspired by commit c8a950d ("tools: Factor HOSTCC, HOSTLD, HOSTAR definitions"). I tested with bpftool and perf on Debian/testing AMD64 and LLVM/Clang v11.1.0-rc1. Build instructions: [ make and make-options ] MAKE="make V=1" MAKE_OPTS="HOSTCC=clang HOSTCXX=clang++ HOSTLD=ld.lld CC=clang LD=ld.lld LLVM=1 LLVM_IAS=1" MAKE_OPTS="$MAKE_OPTS PAHOLE=/opt/pahole/bin/pahole" [ clean-up ] $MAKE $MAKE_OPTS -C tools/ clean [ bpftool ] $MAKE $MAKE_OPTS -C tools/bpf/bpftool/ [ perf ] PYTHON=python3 $MAKE $MAKE_OPTS -C tools/perf/ I was careful with respecting the user's wish to override custom compiler, linker, GNU/binutils and/or LLVM utils settings. Some personal notes: 1. I have NOT tested with cross-toolchain for other archs (cross compiler/linker etc.). 2. This patch is on top of Linux v5.11-rc4. I hope to get some feedback from especially Linux-bpf folks. Acked-by: Jiri Olsa <jolsa@redhat.com> # tools/build and tools/perf Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
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| Master branch: 443edce |
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| At least one diff in series https://patchwork.kernel.org/project/netdevbpf/list/?series=419563 expired. Closing PR. |
kernel-patches-bot pushed a commit that referenced this pull request Feb 4, 2022
Unmapping a fixmap entry is done by calling __set_fixmap() with FIXMAP_PAGE_CLEAR as flags. Today, powerpc __set_fixmap() calls map_kernel_page(). map_kernel_page() is not happy when called a second time for the same page. WARNING: CPU: 0 PID: 1 at arch/powerpc/mm/pgtable.c:194 set_pte_at+0xc/0x1e8 CPU: 0 PID: 1 Comm: swapper Not tainted 5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty #682 NIP: c0017cd4 LR: c00187f0 CTR: 00000010 REGS: e1011d50 TRAP: 0700 Not tainted (5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty) MSR: 00029032 <EE,ME,IR,DR,RI> CR: 42000208 XER: 00000000 GPR00: c0165fec e1011e10 c14c0000 c0ee2550 ff800000 c0f3d000 00000000 c001686c GPR08: 00001000 b00045a9 00000001 c0f58460 c0f50000 00000000 c0007e10 00000000 GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 GPR24: 00000000 00000000 c0ee2550 00000000 c0f57000 00000ff8 00000000 ff800000 NIP [c0017cd4] set_pte_at+0xc/0x1e8 LR [c00187f0] map_kernel_page+0x9c/0x100 Call Trace: [e1011e10] [c0736c68] vsnprintf+0x358/0x6c8 (unreliable) [e1011e30] [c0165fec] __set_fixmap+0x30/0x44 [e1011e40] [c0c13bdc] early_iounmap+0x11c/0x170 [e1011e70] [c0c06cb0] ioremap_legacy_serial_console+0x88/0xc0 [e1011e90] [c0c03634] do_one_initcall+0x80/0x178 [e1011ef0] [c0c0385c] kernel_init_freeable+0xb4/0x250 [e1011f20] [c0007e34] kernel_init+0x24/0x140 [e1011f30] [c0016268] ret_from_kernel_thread+0x5c/0x64 Instruction dump: 7fe3fb78 48019689 80010014 7c630034 83e1000c 5463d97e 7c0803a6 38210010 4e800020 81250000 712a0001 41820008 <0fe00000> 9421ffe0 93e1001c 48000030 Implement unmap_kernel_page() which clears an existing pte. Reported-by: Maxime Bizon <mbizon@freebox.fr> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Tested-by: Maxime Bizon <mbizon@freebox.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b0b752f6f6ecc60653e873f385c6f0dce4e9ab6a.1638789098.git.christophe.leroy@csgroup.eu
kernel-patches-bot pushed a commit that referenced this pull request Apr 27, 2022
…ev_master_upper_dev_get_rcu Next patch uses l3mdev_master_upper_ifindex_by_index_rcu which throws a splat with debug kernels: [13783.087570] ------------[ cut here ]------------ [13783.093974] RTNL: assertion failed at net/core/dev.c (6702) [13783.100761] WARNING: CPU: 3 PID: 51132 at net/core/dev.c:6702 netdev_master_upper_dev_get+0x16a/0x1a0 [13783.184226] CPU: 3 PID: 51132 Comm: kworker/3:3 Not tainted 5.17.0-custom-100090-g6f963aafb1cc #682 [13783.194788] Hardware name: Mellanox Technologies Ltd. MSN2010/SA002610, BIOS 5.6.5 08/24/2017 [13783.204755] Workqueue: mld mld_ifc_work [ipv6] [13783.210338] RIP: 0010:netdev_master_upper_dev_get+0x16a/0x1a0 [13783.217209] Code: 0f 85 e3 fe ff ff e8 65 ac ec fe ba 2e 1a 00 00 48 c7 c6 60 6f 38 83 48 c7 c7 c0 70 38 83 c6 05 5e b5 d7 01 01 e8 c6 29 52 00 <0f> 0b e9 b8 fe ff ff e8 5a 6c 35 ff e9 1c ff ff ff 48 89 ef e8 7d [13783.238659] RSP: 0018:ffffc9000b37f5a8 EFLAGS: 00010286 [13783.244995] RAX: 0000000000000000 RBX: ffff88812ee5c000 RCX: 0000000000000000 [13783.253379] RDX: ffff88811ce09d40 RSI: ffffffff812d0fcd RDI: fffff5200166fea7 [13783.261769] RBP: 0000000000000000 R08: 0000000000000001 R09: ffff8882375f4287 [13783.270138] R10: ffffed1046ebe850 R11: 0000000000000001 R12: dffffc0000000000 [13783.278510] R13: 0000000000000275 R14: ffffc9000b37f688 R15: ffff8881273b4af8 [13783.286870] FS: 0000000000000000(0000) GS:ffff888237400000(0000) knlGS:0000000000000000 [13783.296352] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [13783.303177] CR2: 00007ff25fc9b2e8 CR3: 0000000174d23000 CR4: 00000000001006e0 [13783.311546] Call Trace: [13783.314660] <TASK> [13783.317553] l3mdev_master_upper_ifindex_by_index_rcu+0x43/0xe0 ... Change l3mdev_master_upper_ifindex_by_index_rcu to use netdev_master_upper_dev_get_rcu. Fixes: 6a6d668 ("l3mdev: add function to retreive upper master") Signed-off-by: Ido Schimmel <idosch@idosch.org> Signed-off-by: David Ahern <dsahern@kernel.org> Cc: Alexis Bauvin <abauvin@scaleway.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Nov 9, 2023
Getting the following splat [1] with CONFIG_DEBUG_NET=y and this reproducer [2]. Problem seems to be that classifiers clear 'struct tcf_result::drop_reason', thereby triggering the warning in __kfree_skb_reason() due to reason being 'SKB_NOT_DROPPED_YET' (0). Fixed by disambiguating a legit error from a verdict with a bogus drop_reason [1] WARNING: CPU: 0 PID: 181 at net/core/skbuff.c:1082 kfree_skb_reason+0x38/0x130 Modules linked in: CPU: 0 PID: 181 Comm: mausezahn Not tainted 6.6.0-rc6-custom-ge43e6d9582e0 #682 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-1.fc37 04/01/2014 RIP: 0010:kfree_skb_reason+0x38/0x130 [...] Call Trace: <IRQ> __netif_receive_skb_core.constprop.0+0x837/0xdb0 __netif_receive_skb_one_core+0x3c/0x70 process_backlog+0x95/0x130 __napi_poll+0x25/0x1b0 net_rx_action+0x29b/0x310 __do_softirq+0xc0/0x29b do_softirq+0x43/0x60 </IRQ> [2] ip link add name veth0 type veth peer name veth1 ip link set dev veth0 up ip link set dev veth1 up tc qdisc add dev veth1 clsact tc filter add dev veth1 ingress pref 1 proto all flower dst_mac 00:11:22:33:44:55 action drop mausezahn veth0 -a own -b 00:11:22:33:44:55 -q -c 1 Ido reported: [...] getting the following splat [1] with CONFIG_DEBUG_NET=y and this reproducer [2]. Problem seems to be that classifiers clear 'struct tcf_result::drop_reason', thereby triggering the warning in __kfree_skb_reason() due to reason being 'SKB_NOT_DROPPED_YET' (0). [...] [1] WARNING: CPU: 0 PID: 181 at net/core/skbuff.c:1082 kfree_skb_reason+0x38/0x130 Modules linked in: CPU: 0 PID: 181 Comm: mausezahn Not tainted 6.6.0-rc6-custom-ge43e6d9582e0 #682 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-1.fc37 04/01/2014 RIP: 0010:kfree_skb_reason+0x38/0x130 [...] Call Trace: <IRQ> __netif_receive_skb_core.constprop.0+0x837/0xdb0 __netif_receive_skb_one_core+0x3c/0x70 process_backlog+0x95/0x130 __napi_poll+0x25/0x1b0 net_rx_action+0x29b/0x310 __do_softirq+0xc0/0x29b do_softirq+0x43/0x60 </IRQ> [2] #!/bin/bash ip link add name veth0 type veth peer name veth1 ip link set dev veth0 up ip link set dev veth1 up tc qdisc add dev veth1 clsact tc filter add dev veth1 ingress pref 1 proto all flower dst_mac 00:11:22:33:44:55 action drop mausezahn veth0 -a own -b 00:11:22:33:44:55 -q -c 1 What happens is that inside most classifiers the tcf_result is copied over from a filter template e.g. *res = f->res which then implicitly overrides the prior SKB_DROP_REASON_TC_{INGRESS,EGRESS} default drop code which was set via sch_handle_{ingress,egress}() for kfree_skb_reason(). Commit text above copied verbatim from Daniel. The general idea of the patch is not very different from what Ido originally posted but instead done at the cls_api codepath. Fixes: 54a59ae ("net, sched: Make tc-related drop reason more flexible") Reported-by: Ido Schimmel <idosch@idosch.org> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://lore.kernel.org/netdev/ZTjY959R+AFXf3Xy@shredder Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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Pull request for series with
subject: tools: Factor Clang, LLC and LLVM utils definitions
version: 2
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=419563