December 2019 - Linux-kselftest-mirror

[PATCH v8 00/26] mm/gup: track dma-pinned pages: FOLL_PIN

by John Hubbard

Hi, This implements an API naming change (put_user_page*() --> unpin_user_page*()), and also implements tracking of FOLL_PIN pages. It extends that tracking to a few select subsystems. More subsystems will be added in follow up work. Christoph Hellwig, a couple of points of interest: a) I've moved the bulk of the code out of the inline functions, as requested, for the devmap changes (patch 4: "mm: devmap: refactor 1-based refcounting for ZONE_DEVICE pages"). b) Contrary to my earlier response to your review, I have not actually merged patch 23 ("mm/gup: pass flags arg to __gup_device_* functions") into patch 24 ("mm/gup: track FOLL_PIN pages"). This is because I suspect that it's better to avoid making patch 24 any larger and worse to review than it already is. But if you feel strongly about it, I'll combine them anyway. Changes since v7: * Rebased onto Linux 5.5-rc1 * Reworked the grab_page() and try_grab_compound_head(), for API consistency and less diffs (thanks to Jan Kara's reviews). * Added Leon Romanovsky's reviewed-by tags for two of the IB-related patches. * patch 4 refactoring changes, as mentioned above. There is a git repo and branch, for convenience: git@github.com:johnhubbard/linux.git pin_user_pages_tracking_v8 For the remaining list of "changes since version N", those are all in v7, which is here: https://lore.kernel.org/r/20191121071354.456618-1-jhubbard@nvidia.com ============================================================ Overview: This is a prerequisite to solving the problem of proper interactions between file-backed pages, and [R]DMA activities, as discussed in [1], [2], [3], and in a remarkable number of email threads since about 2017. :) A new internal gup flag, FOLL_PIN is introduced, and thoroughly documented in the last patch's Documentation/vm/pin_user_pages.rst. I believe that this will provide a good starting point for doing the layout lease work that Ira Weiny has been working on. That's because these new wrapper functions provide a clean, constrained, systematically named set of functionality that, again, is required in order to even know if a page is "dma-pinned". In contrast to earlier approaches, the page tracking can be incrementally applied to the kernel call sites that, until now, have been simply calling get_user_pages() ("gup"). In other words, opt-in by changing from this: get_user_pages() (sets FOLL_GET) put_page() to this: pin_user_pages() (sets FOLL_PIN) unpin_user_page() ============================================================ Testing: * I've done some overall kernel testing (LTP, and a few other goodies), and some directed testing to exercise some of the changes. And as you can see, gup_benchmark is enhanced to exercise this. Basically, I've been able to runtime test the core get_user_pages() and pin_user_pages() and related routines, but not so much on several of the call sites--but those are generally just a couple of lines changed, each. Not much of the kernel is actually using this, which on one hand reduces risk quite a lot. But on the other hand, testing coverage is low. So I'd love it if, in particular, the Infiniband and PowerPC folks could do a smoke test of this series for me. Runtime testing for the call sites so far is pretty light: * io_uring: Some directed tests from liburing exercise this, and they pass. * process_vm_access.c: A small directed test passes. * gup_benchmark: the enhanced version hits the new gup.c code, and passes. * infiniband: ran "ib_write_bw", which exercises the umem.c changes, but not the other changes. * VFIO: compiles (I'm vowing to set up a run time test soon, but it's not ready just yet) * powerpc: it compiles... * drm/via: compiles... * goldfish: compiles... * net/xdp: compiles... * media/v4l2: compiles... [1] Some slow progress on get_user_pages() (Apr 2, 2019): https://lwn.net/Articles/784574/ [2] DMA and get_user_pages() (LPC: Dec 12, 2018): https://lwn.net/Articles/774411/ [3] The trouble with get_user_pages() (Apr 30, 2018): https://lwn.net/Articles/753027/ Dan Williams (1): mm: Cleanup __put_devmap_managed_page() vs ->page_free() John Hubbard (25): mm/gup: factor out duplicate code from four routines mm/gup: move try_get_compound_head() to top, fix minor issues mm: devmap: refactor 1-based refcounting for ZONE_DEVICE pages goldish_pipe: rename local pin_user_pages() routine mm: fix get_user_pages_remote()'s handling of FOLL_LONGTERM vfio: fix FOLL_LONGTERM use, simplify get_user_pages_remote() call mm/gup: allow FOLL_FORCE for get_user_pages_fast() IB/umem: use get_user_pages_fast() to pin DMA pages mm/gup: introduce pin_user_pages*() and FOLL_PIN goldish_pipe: convert to pin_user_pages() and put_user_page() IB/{core,hw,umem}: set FOLL_PIN via pin_user_pages*(), fix up ODP mm/process_vm_access: set FOLL_PIN via pin_user_pages_remote() drm/via: set FOLL_PIN via pin_user_pages_fast() fs/io_uring: set FOLL_PIN via pin_user_pages() net/xdp: set FOLL_PIN via pin_user_pages() media/v4l2-core: set pages dirty upon releasing DMA buffers media/v4l2-core: pin_user_pages (FOLL_PIN) and put_user_page() conversion vfio, mm: pin_user_pages (FOLL_PIN) and put_user_page() conversion powerpc: book3s64: convert to pin_user_pages() and put_user_page() mm/gup_benchmark: use proper FOLL_WRITE flags instead of hard-coding "1" mm, tree-wide: rename put_user_page*() to unpin_user_page*() mm/gup: pass flags arg to __gup_device_* functions mm/gup: track FOLL_PIN pages mm/gup_benchmark: support pin_user_pages() and related calls selftests/vm: run_vmtests: invoke gup_benchmark with basic FOLL_PIN coverage Documentation/core-api/index.rst | 1 + Documentation/core-api/pin_user_pages.rst | 233 ++++++++ arch/powerpc/mm/book3s64/iommu_api.c | 12 +- drivers/gpu/drm/via/via_dmablit.c | 6 +- drivers/infiniband/core/umem.c | 19 +- drivers/infiniband/core/umem_odp.c | 13 +- drivers/infiniband/hw/hfi1/user_pages.c | 4 +- drivers/infiniband/hw/mthca/mthca_memfree.c | 8 +- drivers/infiniband/hw/qib/qib_user_pages.c | 4 +- drivers/infiniband/hw/qib/qib_user_sdma.c | 8 +- drivers/infiniband/hw/usnic/usnic_uiom.c | 4 +- drivers/infiniband/sw/siw/siw_mem.c | 4 +- drivers/media/v4l2-core/videobuf-dma-sg.c | 8 +- drivers/nvdimm/pmem.c | 6 - drivers/platform/goldfish/goldfish_pipe.c | 35 +- drivers/vfio/vfio_iommu_type1.c | 35 +- fs/io_uring.c | 6 +- include/linux/mm.h | 145 ++++- include/linux/mmzone.h | 2 + include/linux/page_ref.h | 10 + mm/gup.c | 595 +++++++++++++++----- mm/gup_benchmark.c | 74 ++- mm/huge_memory.c | 23 +- mm/hugetlb.c | 15 +- mm/memremap.c | 76 ++- mm/process_vm_access.c | 28 +- mm/swap.c | 24 + mm/vmstat.c | 2 + net/xdp/xdp_umem.c | 4 +- tools/testing/selftests/vm/gup_benchmark.c | 21 +- tools/testing/selftests/vm/run_vmtests | 22 + 31 files changed, 1093 insertions(+), 354 deletions(-) create mode 100644 Documentation/core-api/pin_user_pages.rst -- 2.24.0

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[PATCH] selftests: filesystems/epoll: fix build error

by Shuah Khan

epoll build fails to find pthread lib. Fix Makefile to use LDLIBS instead of LDFLAGS. LDLIBS is the right flag to use here with -l option when invoking ld. gcc -I../../../../../usr/include/ -lpthread epoll_wakeup_test.c -o .../tools/testing/selftests/filesystems/epoll/epoll_wakeup_test /usr/bin/ld: /tmp/ccaZvJUl.o: in function `kill_timeout': epoll_wakeup_test.c:(.text+0x4dd): undefined reference to `pthread_kill' /usr/bin/ld: epoll_wakeup_test.c:(.text+0x4f2): undefined reference to `pthread_kill' /usr/bin/ld: /tmp/ccaZvJUl.o: in function `epoll9': epoll_wakeup_test.c:(.text+0x6382): undefined reference to `pthread_create' /usr/bin/ld: epoll_wakeup_test.c:(.text+0x64d2): undefined reference to `pthread_create' /usr/bin/ld: epoll_wakeup_test.c:(.text+0x6626): undefined reference to `pthread_join' /usr/bin/ld: epoll_wakeup_test.c:(.text+0x684c): undefined reference to `pthread_tryjoin_np' /usr/bin/ld: epoll_wakeup_test.c:(.text+0x6864): undefined reference to `pthread_kill' /usr/bin/ld: epoll_wakeup_test.c:(.text+0x6878): undefined reference to `pthread_join' Signed-off-by: Shuah Khan <skhan(a)linuxfoundation.org> --- tools/testing/selftests/filesystems/epoll/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/filesystems/epoll/Makefile b/tools/testing/selftests/filesystems/epoll/Makefile index e62f3d4f68da..78ae4aaf7141 100644 --- a/tools/testing/selftests/filesystems/epoll/Makefile +++ b/tools/testing/selftests/filesystems/epoll/Makefile @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 CFLAGS += -I../../../../../usr/include/ -LDFLAGS += -lpthread +LDLIBS += -lpthread TEST_GEN_PROGS := epoll_wakeup_test include ../../lib.mk -- 2.20.1

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[PATCH AUTOSEL 4.19 026/177] selftests/bpf: Correct path to include msg + path

by Sasha Levin

From: Ivan Khoronzhuk <ivan.khoronzhuk(a)linaro.org> [ Upstream commit c588146378962786ddeec817f7736a53298a7b01 ] The "path" buf is supposed to contain path + printf msg up to 24 bytes. It will be cut anyway, but compiler generates truncation warns like: " samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c: In function ‘setup_cgroup_environment’: samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c:52:34: warning: ‘/cgroup.controllers’ directive output may be truncated writing 19 bytes into a region of size between 1 and 4097 [-Wformat-truncation=] snprintf(path, sizeof(path), "%s/cgroup.controllers", cgroup_path); ^~~~~~~~~~~~~~~~~~~ samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c:52:2: note: ‘snprintf’ output between 20 and 4116 bytes into a destination of size 4097 snprintf(path, sizeof(path), "%s/cgroup.controllers", cgroup_path); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c:72:34: warning: ‘/cgroup.subtree_control’ directive output may be truncated writing 23 bytes into a region of size between 1 and 4097 [-Wformat-truncation=] snprintf(path, sizeof(path), "%s/cgroup.subtree_control", ^~~~~~~~~~~~~~~~~~~~~~~ cgroup_path); samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c:72:2: note: ‘snprintf’ output between 24 and 4120 bytes into a destination of size 4097 snprintf(path, sizeof(path), "%s/cgroup.subtree_control", cgroup_path); " In order to avoid warns, lets decrease buf size for cgroup workdir on 24 bytes with assumption to include also "/cgroup.subtree_control" to the address. The cut will never happen anyway. Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk(a)linaro.org> Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net> Acked-by: Song Liu <songliubraving(a)fb.com> Link: https://lore.kernel.org/bpf/20191002120404.26962-3-ivan.khoronzhuk@linaro.o… Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/selftests/bpf/cgroup_helpers.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/cgroup_helpers.c b/tools/testing/selftests/bpf/cgroup_helpers.c index cf16948aad4ad..6af24f9a780de 100644 --- a/tools/testing/selftests/bpf/cgroup_helpers.c +++ b/tools/testing/selftests/bpf/cgroup_helpers.c @@ -44,7 +44,7 @@ */ int setup_cgroup_environment(void) { - char cgroup_workdir[PATH_MAX + 1]; + char cgroup_workdir[PATH_MAX - 24]; format_cgroup_path(cgroup_workdir, ""); -- 2.20.1

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[PATCH AUTOSEL 5.4 327/350] libbpf: Fix call relocation offset calculation bug

by Sasha Levin

From: Andrii Nakryiko <andriin(a)fb.com> [ Upstream commit a0d7da26ce86a25e97ae191cb90574ada6daea98 ] When relocating subprogram call, libbpf doesn't take into account relo->text_off, which comes from symbol's value. This generally works fine for subprograms implemented as static functions, but breaks for global functions. Taking a simplified test_pkt_access.c as an example: __attribute__ ((noinline)) static int test_pkt_access_subprog1(volatile struct __sk_buff *skb) { return skb->len * 2; } __attribute__ ((noinline)) static int test_pkt_access_subprog2(int val, volatile struct __sk_buff *skb) { return skb->len + val; } SEC("classifier/test_pkt_access") int test_pkt_access(struct __sk_buff *skb) { if (test_pkt_access_subprog1(skb) != skb->len * 2) return TC_ACT_SHOT; if (test_pkt_access_subprog2(2, skb) != skb->len + 2) return TC_ACT_SHOT; return TC_ACT_UNSPEC; } When compiled, we get two relocations, pointing to '.text' symbol. .text has st_value set to 0 (it points to the beginning of .text section): 0000000000000008 000000050000000a R_BPF_64_32 0000000000000000 .text 0000000000000040 000000050000000a R_BPF_64_32 0000000000000000 .text test_pkt_access_subprog1 and test_pkt_access_subprog2 offsets (targets of two calls) are encoded within call instruction's imm32 part as -1 and 2, respectively: 0000000000000000 test_pkt_access_subprog1: 0: 61 10 00 00 00 00 00 00 r0 = *(u32 *)(r1 + 0) 1: 64 00 00 00 01 00 00 00 w0 <<= 1 2: 95 00 00 00 00 00 00 00 exit 0000000000000018 test_pkt_access_subprog2: 3: 61 10 00 00 00 00 00 00 r0 = *(u32 *)(r1 + 0) 4: 04 00 00 00 02 00 00 00 w0 += 2 5: 95 00 00 00 00 00 00 00 exit 0000000000000000 test_pkt_access: 0: bf 16 00 00 00 00 00 00 r6 = r1 ===> 1: 85 10 00 00 ff ff ff ff call -1 2: bc 01 00 00 00 00 00 00 w1 = w0 3: b4 00 00 00 02 00 00 00 w0 = 2 4: 61 62 00 00 00 00 00 00 r2 = *(u32 *)(r6 + 0) 5: 64 02 00 00 01 00 00 00 w2 <<= 1 6: 5e 21 08 00 00 00 00 00 if w1 != w2 goto +8 <LBB0_3> 7: bf 61 00 00 00 00 00 00 r1 = r6 ===> 8: 85 10 00 00 02 00 00 00 call 2 9: bc 01 00 00 00 00 00 00 w1 = w0 10: 61 62 00 00 00 00 00 00 r2 = *(u32 *)(r6 + 0) 11: 04 02 00 00 02 00 00 00 w2 += 2 12: b4 00 00 00 ff ff ff ff w0 = -1 13: 1e 21 01 00 00 00 00 00 if w1 == w2 goto +1 <LBB0_3> 14: b4 00 00 00 02 00 00 00 w0 = 2 0000000000000078 LBB0_3: 15: 95 00 00 00 00 00 00 00 exit Now, if we compile example with global functions, the setup changes. Relocations are now against specifically test_pkt_access_subprog1 and test_pkt_access_subprog2 symbols, with test_pkt_access_subprog2 pointing 24 bytes into its respective section (.text), i.e., 3 instructions in: 0000000000000008 000000070000000a R_BPF_64_32 0000000000000000 test_pkt_access_subprog1 0000000000000048 000000080000000a R_BPF_64_32 0000000000000018 test_pkt_access_subprog2 Calls instructions now encode offsets relative to function symbols and are both set ot -1: 0000000000000000 test_pkt_access_subprog1: 0: 61 10 00 00 00 00 00 00 r0 = *(u32 *)(r1 + 0) 1: 64 00 00 00 01 00 00 00 w0 <<= 1 2: 95 00 00 00 00 00 00 00 exit 0000000000000018 test_pkt_access_subprog2: 3: 61 20 00 00 00 00 00 00 r0 = *(u32 *)(r2 + 0) 4: 0c 10 00 00 00 00 00 00 w0 += w1 5: 95 00 00 00 00 00 00 00 exit 0000000000000000 test_pkt_access: 0: bf 16 00 00 00 00 00 00 r6 = r1 ===> 1: 85 10 00 00 ff ff ff ff call -1 2: bc 01 00 00 00 00 00 00 w1 = w0 3: b4 00 00 00 02 00 00 00 w0 = 2 4: 61 62 00 00 00 00 00 00 r2 = *(u32 *)(r6 + 0) 5: 64 02 00 00 01 00 00 00 w2 <<= 1 6: 5e 21 09 00 00 00 00 00 if w1 != w2 goto +9 <LBB2_3> 7: b4 01 00 00 02 00 00 00 w1 = 2 8: bf 62 00 00 00 00 00 00 r2 = r6 ===> 9: 85 10 00 00 ff ff ff ff call -1 10: bc 01 00 00 00 00 00 00 w1 = w0 11: 61 62 00 00 00 00 00 00 r2 = *(u32 *)(r6 + 0) 12: 04 02 00 00 02 00 00 00 w2 += 2 13: b4 00 00 00 ff ff ff ff w0 = -1 14: 1e 21 01 00 00 00 00 00 if w1 == w2 goto +1 <LBB2_3> 15: b4 00 00 00 02 00 00 00 w0 = 2 0000000000000080 LBB2_3: 16: 95 00 00 00 00 00 00 00 exit Thus the right formula to calculate target call offset after relocation should take into account relocation's target symbol value (offset within section), call instruction's imm32 offset, and (subtracting, to get relative instruction offset) instruction index of call instruction itself. All that is shifted by number of instructions in main program, given all sub-programs are copied over after main program. Convert few selftests relying on bpf-to-bpf calls to use global functions instead of static ones. Fixes: 48cca7e44f9f ("libbpf: add support for bpf_call") Reported-by: Alexei Starovoitov <ast(a)kernel.org> Signed-off-by: Andrii Nakryiko <andriin(a)fb.com> Acked-by: Yonghong Song <yhs(a)fb.com> Signed-off-by: Alexei Starovoitov <ast(a)kernel.org> Link: https://lore.kernel.org/bpf/20191119224447.3781271-1-andriin@fb.com Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/lib/bpf/libbpf.c | 8 ++++++-- tools/testing/selftests/bpf/progs/test_btf_haskv.c | 4 ++-- tools/testing/selftests/bpf/progs/test_btf_newkv.c | 4 ++-- tools/testing/selftests/bpf/progs/test_btf_nokv.c | 4 ++-- 4 files changed, 12 insertions(+), 8 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index a267cd0c0ce28..6a87ff9936d7b 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1791,9 +1791,13 @@ bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr, pr_warning("incorrect bpf_call opcode\n"); return -LIBBPF_ERRNO__RELOC; } + if (sym.st_value % 8) { + pr_warn("bad call relo offset: %lu\n", sym.st_value); + return -LIBBPF_ERRNO__RELOC; + } prog->reloc_desc[i].type = RELO_CALL; prog->reloc_desc[i].insn_idx = insn_idx; - prog->reloc_desc[i].text_off = sym.st_value; + prog->reloc_desc[i].text_off = sym.st_value / 8; obj->has_pseudo_calls = true; continue; } @@ -3239,7 +3243,7 @@ bpf_program__reloc_text(struct bpf_program *prog, struct bpf_object *obj, prog->section_name); } insn = &prog->insns[relo->insn_idx]; - insn->imm += prog->main_prog_cnt - relo->insn_idx; + insn->imm += relo->text_off + prog->main_prog_cnt - relo->insn_idx; return 0; } diff --git a/tools/testing/selftests/bpf/progs/test_btf_haskv.c b/tools/testing/selftests/bpf/progs/test_btf_haskv.c index e5c79fe0ffdb2..d65c61e64df2f 100644 --- a/tools/testing/selftests/bpf/progs/test_btf_haskv.c +++ b/tools/testing/selftests/bpf/progs/test_btf_haskv.c @@ -25,7 +25,7 @@ struct dummy_tracepoint_args { }; __attribute__((noinline)) -static int test_long_fname_2(struct dummy_tracepoint_args *arg) +int test_long_fname_2(struct dummy_tracepoint_args *arg) { struct ipv_counts *counts; int key = 0; @@ -43,7 +43,7 @@ static int test_long_fname_2(struct dummy_tracepoint_args *arg) } __attribute__((noinline)) -static int test_long_fname_1(struct dummy_tracepoint_args *arg) +int test_long_fname_1(struct dummy_tracepoint_args *arg) { return test_long_fname_2(arg); } diff --git a/tools/testing/selftests/bpf/progs/test_btf_newkv.c b/tools/testing/selftests/bpf/progs/test_btf_newkv.c index 5ee3622ddebb6..8e83317db841f 100644 --- a/tools/testing/selftests/bpf/progs/test_btf_newkv.c +++ b/tools/testing/selftests/bpf/progs/test_btf_newkv.c @@ -33,7 +33,7 @@ struct dummy_tracepoint_args { }; __attribute__((noinline)) -static int test_long_fname_2(struct dummy_tracepoint_args *arg) +int test_long_fname_2(struct dummy_tracepoint_args *arg) { struct ipv_counts *counts; int key = 0; @@ -56,7 +56,7 @@ static int test_long_fname_2(struct dummy_tracepoint_args *arg) } __attribute__((noinline)) -static int test_long_fname_1(struct dummy_tracepoint_args *arg) +int test_long_fname_1(struct dummy_tracepoint_args *arg) { return test_long_fname_2(arg); } diff --git a/tools/testing/selftests/bpf/progs/test_btf_nokv.c b/tools/testing/selftests/bpf/progs/test_btf_nokv.c index 434188c377743..3f44220447594 100644 --- a/tools/testing/selftests/bpf/progs/test_btf_nokv.c +++ b/tools/testing/selftests/bpf/progs/test_btf_nokv.c @@ -23,7 +23,7 @@ struct dummy_tracepoint_args { }; __attribute__((noinline)) -static int test_long_fname_2(struct dummy_tracepoint_args *arg) +int test_long_fname_2(struct dummy_tracepoint_args *arg) { struct ipv_counts *counts; int key = 0; @@ -41,7 +41,7 @@ static int test_long_fname_2(struct dummy_tracepoint_args *arg) } __attribute__((noinline)) -static int test_long_fname_1(struct dummy_tracepoint_args *arg) +int test_long_fname_1(struct dummy_tracepoint_args *arg) { return test_long_fname_2(arg); } -- 2.20.1

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[PATCH AUTOSEL 5.4 307/350] selftests, bpf: Workaround an alu32 sub-register spilling issue

by Sasha Levin

From: Yonghong Song <yhs(a)fb.com> [ Upstream commit 2ea2612b987ad703235c92be21d4e98ee9c2c67c ] Currently, with latest llvm trunk, selftest test_progs failed obj file test_seg6_loop.o with the following error in verifier: infinite loop detected at insn 76 The byte code sequence looks like below, and noted that alu32 has been turned off by default for better generated codes in general: 48: w3 = 100 49: *(u32 *)(r10 - 68) = r3 ... ; if (tlv.type == SR6_TLV_PADDING) { 76: if w3 == 5 goto -18 <LBB0_19> ... 85: r1 = *(u32 *)(r10 - 68) ; for (int i = 0; i < 100; i++) { 86: w1 += -1 87: if w1 == 0 goto +5 <LBB0_20> 88: *(u32 *)(r10 - 68) = r1 The main reason for verification failure is due to partial spills at r10 - 68 for induction variable "i". Current verifier only handles spills with 8-byte values. The above 4-byte value spill to stack is treated to STACK_MISC and its content is not saved. For the above example: w3 = 100 R3_w=inv100 fp-64_w=inv1086626730498 *(u32 *)(r10 - 68) = r3 R3_w=inv100 fp-64_w=inv1086626730498 ... r1 = *(u32 *)(r10 - 68) R1_w=inv(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) fp-64=inv1086626730498 To resolve this issue, verifier needs to be extended to track sub-registers in spilling, or llvm needs to enhanced to prevent sub-register spilling in register allocation phase. The former will increase verifier complexity and the latter will need some llvm "hacking". Let us workaround this issue by declaring the induction variable as "long" type so spilling will happen at non sub-register level. We can revisit this later if sub-register spilling causes similar or other verification issues. Signed-off-by: Yonghong Song <yhs(a)fb.com> Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net> Acked-by: Andrii Nakryiko <andriin(a)fb.com> Link: https://lore.kernel.org/bpf/20191117214036.1309510-1-yhs@fb.com Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/selftests/bpf/progs/test_seg6_loop.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/progs/test_seg6_loop.c b/tools/testing/selftests/bpf/progs/test_seg6_loop.c index c4d104428643e..69880c1e7700c 100644 --- a/tools/testing/selftests/bpf/progs/test_seg6_loop.c +++ b/tools/testing/selftests/bpf/progs/test_seg6_loop.c @@ -132,8 +132,10 @@ static __always_inline int is_valid_tlv_boundary(struct __sk_buff *skb, *pad_off = 0; // we can only go as far as ~10 TLVs due to the BPF max stack size + // workaround: define induction variable "i" as "long" instead + // of "int" to prevent alu32 sub-register spilling. #pragma clang loop unroll(disable) - for (int i = 0; i < 100; i++) { + for (long i = 0; i < 100; i++) { struct sr6_tlv_t tlv; if (cur_off == *tlv_off) -- 2.20.1

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[PATCH AUTOSEL 5.4 306/350] selftests, bpf: Fix test_tc_tunnel hanging

by Sasha Levin

From: Jiri Benc <jbenc(a)redhat.com> [ Upstream commit 3b054b7133b4ad93671c82e8d6185258e3f1a7a5 ] When run_kselftests.sh is run, it hangs after test_tc_tunnel.sh. The reason is test_tc_tunnel.sh ensures the server ('nc -l') is run all the time, starting it again every time it is expected to terminate. The exception is the final client_connect: the server is not started anymore, which ensures no process is kept running after the test is finished. For a sit test, though, the script is terminated prematurely without the final client_connect and the 'nc' process keeps running. This in turn causes the run_one function in kselftest/runner.sh to hang forever, waiting for the runaway process to finish. Ensure a remaining server is terminated on cleanup. Fixes: f6ad6accaa99 ("selftests/bpf: expand test_tc_tunnel with SIT encap") Signed-off-by: Jiri Benc <jbenc(a)redhat.com> Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net> Acked-by: Willem de Bruijn <willemb(a)google.com> Link: https://lore.kernel.org/bpf/60919291657a9ee89c708d8aababc28ebe1420be.157382… Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/selftests/bpf/test_tc_tunnel.sh | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/tools/testing/selftests/bpf/test_tc_tunnel.sh b/tools/testing/selftests/bpf/test_tc_tunnel.sh index ff0d31d38061f..7c76b841b17bb 100755 --- a/tools/testing/selftests/bpf/test_tc_tunnel.sh +++ b/tools/testing/selftests/bpf/test_tc_tunnel.sh @@ -62,6 +62,10 @@ cleanup() { if [[ -f "${infile}" ]]; then rm "${infile}" fi + + if [[ -n $server_pid ]]; then + kill $server_pid 2> /dev/null + fi } server_listen() { @@ -77,6 +81,7 @@ client_connect() { verify_data() { wait "${server_pid}" + server_pid= # sha1sum returns two fields [sha1] [filepath] # convert to bash array and access first elem insum=($(sha1sum ${infile})) -- 2.20.1

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[PATCH AUTOSEL 5.4 267/350] bpf, testing: Workaround a verifier failure for test_progs

by Sasha Levin

From: Yonghong Song <yhs(a)fb.com> [ Upstream commit b7a0d65d80a0c5034b366392624397a0915b7556 ] With latest llvm compiler, running test_progs will have the following verifier failure for test_sysctl_loop1.o: libbpf: load bpf program failed: Permission denied libbpf: -- BEGIN DUMP LOG --- libbpf: invalid indirect read from stack var_off (0x0; 0xff)+196 size 7 ... libbpf: -- END LOG -- libbpf: failed to load program 'cgroup/sysctl' libbpf: failed to load object 'test_sysctl_loop1.o' The related bytecode looks as below: 0000000000000308 LBB0_8: 97: r4 = r10 98: r4 += -288 99: r4 += r7 100: w8 &= 255 101: r1 = r10 102: r1 += -488 103: r1 += r8 104: r2 = 7 105: r3 = 0 106: call 106 107: w1 = w0 108: w1 += -1 109: if w1 > 6 goto -24 <LBB0_5> 110: w0 += w8 111: r7 += 8 112: w8 = w0 113: if r7 != 224 goto -17 <LBB0_8> And source code: for (i = 0; i < ARRAY_SIZE(tcp_mem); ++i) { ret = bpf_strtoul(value + off, MAX_ULONG_STR_LEN, 0, tcp_mem + i); if (ret <= 0 || ret > MAX_ULONG_STR_LEN) return 0; off += ret & MAX_ULONG_STR_LEN; } Current verifier is not able to conclude that register w0 before '+' at insn 110 has a range of 1 to 7 and thinks it is from 0 - 255. This leads to more conservative range for w8 at insn 112, and later verifier complaint. Let us workaround this issue until we found a compiler and/or verifier solution. The workaround in this patch is to make variable 'ret' volatile, which will force a reload and then '&' operation to ensure better value range. With this patch, I got the below byte code for the loop: 0000000000000328 LBB0_9: 101: r4 = r10 102: r4 += -288 103: r4 += r7 104: w8 &= 255 105: r1 = r10 106: r1 += -488 107: r1 += r8 108: r2 = 7 109: r3 = 0 110: call 106 111: *(u32 *)(r10 - 64) = r0 112: r1 = *(u32 *)(r10 - 64) 113: if w1 s< 1 goto -28 <LBB0_5> 114: r1 = *(u32 *)(r10 - 64) 115: if w1 s> 7 goto -30 <LBB0_5> 116: r1 = *(u32 *)(r10 - 64) 117: w1 &= 7 118: w1 += w8 119: r7 += 8 120: w8 = w1 121: if r7 != 224 goto -21 <LBB0_9> Insn 117 did the '&' operation and we got more precise value range for 'w8' at insn 120. The test is happy then: #3/17 test_sysctl_loop1.o:OK Signed-off-by: Yonghong Song <yhs(a)fb.com> Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net> Acked-by: Song Liu <songliubraving(a)fb.com> Link: https://lore.kernel.org/bpf/20191107170045.2503480-1-yhs@fb.com Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/selftests/bpf/progs/test_sysctl_loop1.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/progs/test_sysctl_loop1.c b/tools/testing/selftests/bpf/progs/test_sysctl_loop1.c index 608a06871572d..d22e438198cf7 100644 --- a/tools/testing/selftests/bpf/progs/test_sysctl_loop1.c +++ b/tools/testing/selftests/bpf/progs/test_sysctl_loop1.c @@ -44,7 +44,10 @@ int sysctl_tcp_mem(struct bpf_sysctl *ctx) unsigned long tcp_mem[TCP_MEM_LOOPS] = {}; char value[MAX_VALUE_STR_LEN]; unsigned char i, off = 0; - int ret; + /* a workaround to prevent compiler from generating + * codes verifier cannot handle yet. + */ + volatile int ret; if (ctx->write) return 0; -- 2.20.1

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[PATCH AUTOSEL 5.4 250/350] selftests: net: Fix printf format warnings on arm

by Sasha Levin

From: Masami Hiramatsu <mhiramat(a)kernel.org> [ Upstream commit 670cd6849ea36ea4df2f2941cf4717dff8755abe ] Fix printf format warnings on arm (and other 32bit arch). - udpgso.c and udpgso_bench_tx use %lu for size_t but it should be unsigned long long on 32bit arch. - so_txtime.c uses %ld for int64_t, but it should be unsigned long long on 32bit arch. Signed-off-by: Masami Hiramatsu <mhiramat(a)kernel.org> Cc: Willem de Bruijn <willemb(a)google.com> Cc: David S. Miller <davem(a)davemloft.net> Signed-off-by: Shuah Khan <skhan(a)linuxfoundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/selftests/net/so_txtime.c | 4 ++-- tools/testing/selftests/net/udpgso.c | 3 ++- tools/testing/selftests/net/udpgso_bench_tx.c | 3 ++- 3 files changed, 6 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/net/so_txtime.c b/tools/testing/selftests/net/so_txtime.c index 53f598f066470..34df4c8882afb 100644 --- a/tools/testing/selftests/net/so_txtime.c +++ b/tools/testing/selftests/net/so_txtime.c @@ -105,8 +105,8 @@ static void do_recv_one(int fdr, struct timed_send *ts) tstop = (gettime_ns() - glob_tstart) / 1000; texpect = ts->delay_us >= 0 ? ts->delay_us : 0; - fprintf(stderr, "payload:%c delay:%ld expected:%ld (us)\n", - rbuf[0], tstop, texpect); + fprintf(stderr, "payload:%c delay:%lld expected:%lld (us)\n", + rbuf[0], (long long)tstop, (long long)texpect); if (rbuf[0] != ts->data) error(1, 0, "payload mismatch. expected %c", ts->data); diff --git a/tools/testing/selftests/net/udpgso.c b/tools/testing/selftests/net/udpgso.c index 614b31aad168b..c66da6ffd6d8d 100644 --- a/tools/testing/selftests/net/udpgso.c +++ b/tools/testing/selftests/net/udpgso.c @@ -440,7 +440,8 @@ static bool __send_one(int fd, struct msghdr *msg, int flags) if (ret == -1) error(1, errno, "sendmsg"); if (ret != msg->msg_iov->iov_len) - error(1, 0, "sendto: %d != %lu", ret, msg->msg_iov->iov_len); + error(1, 0, "sendto: %d != %llu", ret, + (unsigned long long)msg->msg_iov->iov_len); if (msg->msg_flags) error(1, 0, "sendmsg: return flags 0x%x\n", msg->msg_flags); diff --git a/tools/testing/selftests/net/udpgso_bench_tx.c b/tools/testing/selftests/net/udpgso_bench_tx.c index ada99496634aa..17512a43885e7 100644 --- a/tools/testing/selftests/net/udpgso_bench_tx.c +++ b/tools/testing/selftests/net/udpgso_bench_tx.c @@ -405,7 +405,8 @@ static int send_udp_segment(int fd, char *data) if (ret == -1) error(1, errno, "sendmsg"); if (ret != iov.iov_len) - error(1, 0, "sendmsg: %u != %lu\n", ret, iov.iov_len); + error(1, 0, "sendmsg: %u != %llu\n", ret, + (unsigned long long)iov.iov_len); return 1; } -- 2.20.1

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[PATCH AUTOSEL 5.4 245/350] selftests: proc: Make va_max 1MB

by Sasha Levin

From: Masami Hiramatsu <mhiramat(a)kernel.org> [ Upstream commit 2f3571ea71311bbb2cbb9c3bbefc9c1969a3e889 ] Currently proc-self-map-files-002.c sets va_max (max test address of user virtual address) to 4GB, but it is too big for 32bit arch and 1UL << 32 is overflow on 32bit long. Also since this value should be enough bigger than vm.mmap_min_addr (64KB or 32KB by default), 1MB should be enough. Make va_max 1MB unconditionally. Signed-off-by: Masami Hiramatsu <mhiramat(a)kernel.org> Cc: Alexey Dobriyan <adobriyan(a)gmail.com> Signed-off-by: Shuah Khan <skhan(a)linuxfoundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/selftests/proc/proc-self-map-files-002.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/proc/proc-self-map-files-002.c b/tools/testing/selftests/proc/proc-self-map-files-002.c index 47b7473dedef7..e6aa00a183bcd 100644 --- a/tools/testing/selftests/proc/proc-self-map-files-002.c +++ b/tools/testing/selftests/proc/proc-self-map-files-002.c @@ -47,7 +47,11 @@ static void fail(const char *fmt, unsigned long a, unsigned long b) int main(void) { const int PAGE_SIZE = sysconf(_SC_PAGESIZE); - const unsigned long va_max = 1UL << 32; + /* + * va_max must be enough bigger than vm.mmap_min_addr, which is + * 64KB/32KB by default. (depends on CONFIG_LSM_MMAP_MIN_ADDR) + */ + const unsigned long va_max = 1UL << 20; unsigned long va; void *p; int fd; -- 2.20.1

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[PATCH AUTOSEL 5.4 132/350] selftests/bpf: Make a copy of subtest name

by Sasha Levin

From: Andrii Nakryiko <andriin(a)fb.com> [ Upstream commit f90415e9600c5227131531c0ed11514a2d3bbe62 ] test_progs never created a copy of subtest name, rather just stored pointer to whatever string test provided. This is bad as that string might be freed or modified by the end of subtest. Fix this by creating a copy of given subtest name when subtest starts. Signed-off-by: Andrii Nakryiko <andriin(a)fb.com> Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net> Link: https://lore.kernel.org/bpf/20191021033902.3856966-6-andriin@fb.com Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/selftests/bpf/test_progs.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c index af75a1c7a4587..3bf18364c67c9 100644 --- a/tools/testing/selftests/bpf/test_progs.c +++ b/tools/testing/selftests/bpf/test_progs.c @@ -20,7 +20,7 @@ struct prog_test_def { bool tested; bool need_cgroup_cleanup; - const char *subtest_name; + char *subtest_name; int subtest_num; /* store counts before subtest started */ @@ -81,16 +81,17 @@ void test__end_subtest() fprintf(env.stdout, "#%d/%d %s:%s\n", test->test_num, test->subtest_num, test->subtest_name, sub_error_cnt ? "FAIL" : "OK"); + + free(test->subtest_name); + test->subtest_name = NULL; } bool test__start_subtest(const char *name) { struct prog_test_def *test = env.test; - if (test->subtest_name) { + if (test->subtest_name) test__end_subtest(); - test->subtest_name = NULL; - } test->subtest_num++; @@ -104,7 +105,13 @@ bool test__start_subtest(const char *name) if (!should_run(&env.subtest_selector, test->subtest_num, name)) return false; - test->subtest_name = name; + test->subtest_name = strdup(name); + if (!test->subtest_name) { + fprintf(env.stderr, + "Subtest #%d: failed to copy subtest name!\n", + test->subtest_num); + return false; + } env.test->old_error_cnt = env.test->error_cnt; return true; -- 2.20.1

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Linux-kselftest-mirror December 2019