From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 70CBD3CB8E6; Fri, 3 Jul 2026 11:51:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783079519; cv=none; b=KWtNpO0apHe36L9McsR/5vFI4+ND2N+aYYQXREUPrww3MY+M/9QEV68zbuxrJ/k4yFm49RA6sJ/zUCTE/7dUu5yIGYh2FvkiDK1TmgImudLK09jkDEfVUfiLnusH7OpE9bXWQT5i8pLNi0PLHMs0wdhEXSMVAKMNt1jI4Vq7Otk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783079519; c=relaxed/simple; bh=uS+uBU0I1YUlE+u2cEASKbRadtgcrgEbwbFoMh4+Xh0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OqZtiCOsV77pBqYJS2c2gyJtVE2s3TRk5skjZUCorGBC4/sAF5scaMoWDo0CWVN5txqSeHhWXNq1fYhLy4dGzcGQouLBuXdGSAcuKggjQha5BJLcat5YGUTxONaatI1RFB9WiGokV2e106TaMTTg/5bA28z+xcrWqEmqeB2+0NM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bD1zbKxt; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bD1zbKxt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7A18F1F000E9; Fri, 3 Jul 2026 11:51:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783079518; bh=RQchSe69DAW2imVyaCUfe1AzsIA6bhxFsqyxnFs71Ws=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=bD1zbKxt2NWCSbGz3TEihCl8RMn7YbwnIaxITuNIjS429bfBNF/JzdTrD0RZN04Q5 3RUZFlLiPq7mmJ5d4OGG/vu/FQH1PzjJK8B4sZvtWQiPFH8cCmA1pHsrCTrbBEsadT DM5kgoxtyE1hRjIZjiIPG0J8saVXHscoKPHGEo1XuQW60cBhiQ3deBVhOMDW+1DJzF BEhw7XK7ppkWoHPf9Y3qcuL1Z8x7FQL6Kn13FY2aj5a4GBia54aLZfSgJp/nY3mgJf 6bwWPiLAkQZFUxcA4Hovlau5PveNLCbmAWPXSb/euqEnzZM1o1jBxPsy6hA9XV3Mq6 gSTMiBf3dnNAg== From: Jiri Olsa To: Oleg Nesterov , Peter Zijlstra , Ingo Molnar , Masami Hiramatsu , Andrii Nakryiko Cc: Jakub Sitnicki , bpf@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCHv6 13/13] selftests/bpf: Add tests for forked/cloned optimized uprobes Date: Fri, 3 Jul 2026 13:49:17 +0200 Message-ID: <20260703114917.238144-14-jolsa@kernel.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260703114917.238144-1-jolsa@kernel.org> References: <20260703114917.238144-1-jolsa@kernel.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Adding tests for forked/cloned optimized uprobes and make sure the child can properly execute optimized probe for both fork (dups mm) and clone with CLONE_VM. Reviewed-by: Jakub Sitnicki Signed-off-by: Jiri Olsa --- .../selftests/bpf/prog_tests/uprobe_syscall.c | 88 +++++++++++++++++++ 1 file changed, 88 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c index ff07e5df9a65..e193206fc5d2 100644 --- a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c +++ b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c @@ -4,6 +4,8 @@ #ifdef __x86_64__ +#define _GNU_SOURCE +#include #include #include #include @@ -13,6 +15,7 @@ #include #include #include +#include #include "uprobe_syscall.skel.h" #include "uprobe_syscall_executed.skel.h" #include "bpf/libbpf_internal.h" @@ -954,6 +957,87 @@ static void test_uprobe_error(void) ASSERT_EQ(errno, EPROTO, "errno"); } +__attribute__((aligned(16))) +__nocf_check __weak __naked void uprobe_fork_test(void) +{ + asm volatile ( + ".byte 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00\n" /* nop10 */ + "ret\n" + ); +} + +static noreturn int child_func(void *arg) +{ + struct uprobe_syscall_executed *skel = arg; + + /* Make sure the child's probe is still there and optimized.. */ + if (memcmp(uprobe_fork_test, lea_rsp, sizeof(lea_rsp))) + _exit(1); + + skel->bss->pid = getpid(); + + /* .. and it executes properly. */ + uprobe_fork_test(); + + if (skel->bss->executed != 3) + _exit(2); + + _exit(0); +} + +static void test_uprobe_fork_optimized(bool clone_vm) +{ + struct uprobe_syscall_executed *skel = NULL; + unsigned long offset; + int pid, status, err; + char stack[65535]; + + offset = get_uprobe_offset(&uprobe_fork_test); + if (!ASSERT_GE(offset, 0, "get_uprobe_offset")) + return; + + skel = uprobe_syscall_executed__open_and_load(); + if (!ASSERT_OK_PTR(skel, "open_and_load")) + goto cleanup; + + skel->links.test_uprobe = bpf_program__attach_uprobe_opts(skel->progs.test_uprobe, + -1, "/proc/self/exe", offset, NULL); + if (!ASSERT_OK_PTR(skel->links.test_uprobe, "attach_uprobe")) + goto cleanup; + + skel->bss->pid = getpid(); + + /* Trigger optimization of uprobe in uprobe_fork_test. */ + uprobe_fork_test(); + uprobe_fork_test(); + + /* Make sure it got optimied. */ + if (!ASSERT_OK(memcmp(uprobe_fork_test, lea_rsp, sizeof(lea_rsp)), "optimized")) + goto cleanup; + + if (clone_vm) { + pid = clone(child_func, stack + sizeof(stack), CLONE_VM|SIGCHLD, skel); + if (!ASSERT_GT(pid, 0, "clone")) + goto cleanup; + } else { + pid = fork(); + if (!ASSERT_GE(pid, 0, "fork")) + goto cleanup; + if (pid == 0) + child_func(skel); + } + + /* Wait for the child and verify it exited properly with 0. */ + err = waitpid(pid, &status, 0); + if (ASSERT_EQ(err, pid, "waitpid")) { + ASSERT_EQ(WIFEXITED(status), 1, "child_exited"); + ASSERT_EQ(WEXITSTATUS(status), 0, "child_exit_code"); + } + +cleanup: + uprobe_syscall_executed__destroy(skel); +} + static void __test_uprobe_syscall(void) { if (test__start_subtest("uretprobe_regs_equal")) @@ -974,6 +1058,10 @@ static void __test_uprobe_syscall(void) test_uprobe_race(); if (test__start_subtest("uprobe_red_zone")) test_uprobe_red_zone(); + if (test__start_subtest("uprobe_optimized_fork")) + test_uprobe_fork_optimized(false); + if (test__start_subtest("uprobe_optimized_clone_vm")) + test_uprobe_fork_optimized(true); if (test__start_subtest("uprobe_error")) test_uprobe_error(); if (test__start_subtest("uprobe_regs_equal")) -- 2.54.0