From nobody Mon Feb 9 17:22:33 2026 Received: from madrid.collaboradmins.com (madrid.collaboradmins.com [46.235.227.194]) (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 51DBD13C9A4; Fri, 12 Jul 2024 08:47:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=46.235.227.194 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720774047; cv=none; b=nFf0xbc18ZrZ8seGIkULhuaMtaj//vWIkdeWq4Kx5ohAXcqEviOUSrYLrPGLTSZBvrC1TtGQIXDgC3VT1+Q4ux0PxfO5Pc9x4H2OCYFzlOfbJSTbLbhMhdiWrOJuWo6lWuhB1PB60glwJtjnK//PBSNz6rKmGAV0OpiBdhyys1Q= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720774047; c=relaxed/simple; bh=3MDi7FHmO1ZC5BgTBljZuDhp6QNlf+5LjqAVlUaXsWE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=SWj0LeGo3+QNBDDwg6slm30CbH/uJTh2m25x1n0cNhIjdgOGDgLLq4YJNvzlluKXsJ429A/XS9TYvHo5DGZZDHo4Uuj5dL8Wqml/6845Rw7DrFntMszRQd6lww/SESs1U3MJt0RWVNSWBYsAGh2hg5494k5wMmW++6aZd4uk/go= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=NGj2JXKv; arc=none smtp.client-ip=46.235.227.194 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="NGj2JXKv" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1720774043; bh=3MDi7FHmO1ZC5BgTBljZuDhp6QNlf+5LjqAVlUaXsWE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NGj2JXKvfBR7Fd9KyLP4JcOHtP4XwAkKTelQwJ6eayIDOTOsZ6SuMM3gAnDWhLPba hufmoAUzDuWJAWydjDhvLDDMEKEJ0gQr8zm1VxZ82CYo2mGKMNVEDQLzW8uH6hmVNI EnYI+CIdFYT9Xax2QB2IstlKbBd3j9Be0ivfUS5oMjcziPsWr6c22gbzR3L+s4DWtw 1jZK/TTpjLPBmlEIxHx+hZRlfFaQBB42wDHtxdcbHiktIh/pYDLw1/5tsyohaAnqPF +m87TlClSQE+vas3UP84cdrwk1r0jRaRIyWv1wKOE4veTW+jxT8paRvxy5mbl3ivQF pXDNGdsunfQ4w== Received: from localhost.localdomain (ec2-34-240-57-77.eu-west-1.compute.amazonaws.com [34.240.57.77]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: usama.anjum) by madrid.collaboradmins.com (Postfix) with ESMTPSA id B90B33782212; Fri, 12 Jul 2024 08:47:20 +0000 (UTC) From: Muhammad Usama Anjum To: Shuah Khan , Muhammad Usama Anjum , linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, John Hubbard Cc: kernel@collabora.com, "Chang S . Bae" , Binbin Wu , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan Subject: [PATCH v2 3/4] selftests: x86: fsgsbase_restore: remove manual counting and increase maintainability Date: Fri, 12 Jul 2024 13:46:24 +0500 Message-Id: <20240712084625.297249-4-usama.anjum@collabora.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240712084625.297249-1-usama.anjum@collabora.com> References: <20240712084625.297249-1-usama.anjum@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" - Add test skip support instead of returning success at skip time for the kselftest script to understand correct exit status - Print details about errno if error occurs - Increase readability and maintainability - Print logs in standard format Signed-off-by: Muhammad Usama Anjum --- .../testing/selftests/x86/fsgsbase_restore.c | 117 +++++++++--------- 1 file changed, 57 insertions(+), 60 deletions(-) diff --git a/tools/testing/selftests/x86/fsgsbase_restore.c b/tools/testing= /selftests/x86/fsgsbase_restore.c index 224058c1e4b2e..ef326c08d3508 100644 --- a/tools/testing/selftests/x86/fsgsbase_restore.c +++ b/tools/testing/selftests/x86/fsgsbase_restore.c @@ -30,6 +30,7 @@ #include #include #include +#include "../kselftest.h" =20 #define EXPECTED_VALUE 0x1337f00d =20 @@ -45,18 +46,18 @@ */ unsigned int dereference_seg_base(void); =20 -static void init_seg(void) +static int init_seg(void) { unsigned int *target =3D mmap( NULL, sizeof(unsigned int), PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_32BIT, -1, 0); if (target =3D=3D MAP_FAILED) - err(1, "mmap"); + ksft_exit_fail_perror("mmap"); =20 *target =3D EXPECTED_VALUE; =20 - printf("\tsegment base address =3D 0x%lx\n", (unsigned long)target); + ksft_print_msg("segment base address =3D 0x%lx\n", (unsigned long)target); =20 struct user_desc desc =3D { .entry_number =3D 0, @@ -70,7 +71,7 @@ static void init_seg(void) .useable =3D 0 }; if (syscall(SYS_modify_ldt, 1, &desc, sizeof(desc)) =3D=3D 0) { - printf("\tusing LDT slot 0\n"); + ksft_print_msg("using LDT slot 0\n"); asm volatile ("mov %0, %" SEG :: "rm" ((unsigned short)0x7)); } else { /* No modify_ldt for us (configured out, perhaps) */ @@ -96,14 +97,16 @@ static void init_seg(void) munmap(low_desc, sizeof(desc)); =20 if (ret !=3D 0) { - printf("[NOTE]\tcould not create a segment -- can't test anything\n"); - exit(0); + ksft_print_msg("could not create a segment -- can't test anything\n"); + return KSFT_SKIP; } - printf("\tusing GDT slot %d\n", desc.entry_number); + ksft_print_msg("using GDT slot %d\n", desc.entry_number); =20 unsigned short sel =3D (unsigned short)((desc.entry_number << 3) | 0x3); asm volatile ("mov %0, %" SEG :: "rm" (sel)); } + + return 0; } =20 static void tracee_zap_segment(void) @@ -114,7 +117,7 @@ static void tracee_zap_segment(void) * we modify a segment register in order to make sure that ptrace * can correctly restore segment registers. */ - printf("\tTracee: in tracee_zap_segment()\n"); + ksft_print_msg("Tracee: in tracee_zap_segment()\n"); =20 /* * Write a nonzero selector with base zero to the segment register. @@ -129,70 +132,72 @@ static void tracee_zap_segment(void) =20 pid_t pid =3D getpid(), tid =3D syscall(SYS_gettid); =20 - printf("\tTracee is going back to sleep\n"); + ksft_print_msg("Tracee is going back to sleep\n"); syscall(SYS_tgkill, pid, tid, SIGSTOP); =20 /* Should not get here. */ - while (true) { - printf("[FAIL]\tTracee hit unreachable code\n"); - pause(); - } + ksft_exit_fail_msg("Tracee hit unreachable code\n"); } =20 int main() { - printf("\tSetting up a segment\n"); - init_seg(); + int ret; + + ksft_print_header(); + ksft_set_plan(2); + + ksft_print_msg("Setting up a segment\n"); + + ret =3D init_seg(); + if (ret) + return ret; =20 unsigned int val =3D dereference_seg_base(); - if (val !=3D EXPECTED_VALUE) { - printf("[FAIL]\tseg[0] =3D=3D %x; should be %x\n", val, EXPECTED_VALUE); - return 1; - } - printf("[OK]\tThe segment points to the right place.\n"); + ksft_test_result(val =3D=3D EXPECTED_VALUE, "The segment points to the ri= ght place.\n"); =20 pid_t chld =3D fork(); if (chld < 0) - err(1, "fork"); + ksft_exit_fail_perror("fork"); =20 if (chld =3D=3D 0) { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0, 0); =20 if (ptrace(PTRACE_TRACEME, 0, 0, 0) !=3D 0) - err(1, "PTRACE_TRACEME"); + ksft_exit_fail_perror("PTRACE_TRACEME"); =20 pid_t pid =3D getpid(), tid =3D syscall(SYS_gettid); =20 - printf("\tTracee will take a nap until signaled\n"); + ksft_print_msg("Tracee will take a nap until signaled\n"); syscall(SYS_tgkill, pid, tid, SIGSTOP); =20 - printf("\tTracee was resumed. Will re-check segment.\n"); + ksft_print_msg("Tracee was resumed. Will re-check segment.\n"); =20 val =3D dereference_seg_base(); - if (val !=3D EXPECTED_VALUE) { - printf("[FAIL]\tseg[0] =3D=3D %x; should be %x\n", val, EXPECTED_VALUE); - exit(1); + + if (val =3D=3D EXPECTED_VALUE) { + ksft_print_msg("The segment points to the right place.\n"); + return EXIT_SUCCESS; } =20 - printf("[OK]\tThe segment points to the right place.\n"); - exit(0); + ksft_print_msg("seg[0] =3D=3D %x; should be %x\n", val, EXPECTED_VALUE); + return EXIT_FAILURE; } =20 int status; =20 /* Wait for SIGSTOP. */ if (waitpid(chld, &status, 0) !=3D chld || !WIFSTOPPED(status)) - err(1, "waitpid"); + ksft_exit_fail_perror("waitpid"); =20 struct user_regs_struct regs; =20 if (ptrace(PTRACE_GETREGS, chld, NULL, ®s) !=3D 0) - err(1, "PTRACE_GETREGS"); + ksft_exit_fail_perror("PTRACE_GETREGS"); =20 #ifdef __x86_64__ - printf("\tChild GS=3D0x%lx, GSBASE=3D0x%lx\n", (unsigned long)regs.gs, (u= nsigned long)regs.gs_base); + ksft_print_msg("Child GS=3D0x%lx, GSBASE=3D0x%lx\n", (unsigned long)regs.= gs, (unsigned long)regs.gs_base); #else - printf("\tChild FS=3D0x%lx\n", (unsigned long)regs.xfs); + ksft_print_msg("Child FS=3D0x%lx\n", (unsigned long)regs.xfs); #endif =20 struct user_regs_struct regs2 =3D regs; @@ -203,42 +208,34 @@ int main() regs2.eip =3D (unsigned long)tracee_zap_segment; #endif =20 - printf("\tTracer: redirecting tracee to tracee_zap_segment()\n"); + ksft_print_msg("Tracer: redirecting tracee to tracee_zap_segment()\n"); if (ptrace(PTRACE_SETREGS, chld, NULL, ®s2) !=3D 0) - err(1, "PTRACE_GETREGS"); + ksft_exit_fail_perror("PTRACE_GETREGS"); if (ptrace(PTRACE_CONT, chld, NULL, NULL) !=3D 0) - err(1, "PTRACE_GETREGS"); + ksft_exit_fail_perror("PTRACE_GETREGS"); =20 /* Wait for SIGSTOP. */ if (waitpid(chld, &status, 0) !=3D chld || !WIFSTOPPED(status)) - err(1, "waitpid"); + ksft_exit_fail_perror("waitpid"); =20 - printf("\tTracer: restoring tracee state\n"); + ksft_print_msg("Tracer: restoring tracee state\n"); if (ptrace(PTRACE_SETREGS, chld, NULL, ®s) !=3D 0) - err(1, "PTRACE_GETREGS"); + ksft_exit_fail_perror("PTRACE_GETREGS"); if (ptrace(PTRACE_DETACH, chld, NULL, NULL) !=3D 0) - err(1, "PTRACE_GETREGS"); + ksft_exit_fail_perror("PTRACE_GETREGS"); =20 /* Wait for SIGSTOP. */ if (waitpid(chld, &status, 0) !=3D chld) - err(1, "waitpid"); - - if (WIFSIGNALED(status)) { - printf("[FAIL]\tTracee crashed\n"); - return 1; - } - - if (!WIFEXITED(status)) { - printf("[FAIL]\tTracee stopped for an unexpected reason: %d\n", status); - return 1; - } - - int exitcode =3D WEXITSTATUS(status); - if (exitcode !=3D 0) { - printf("[FAIL]\tTracee reported failure\n"); - return 1; - } - - printf("[OK]\tAll is well.\n"); - return 0; + ksft_exit_fail_perror("waitpid"); + + if (WIFSIGNALED(status)) + ksft_test_result_fail("Tracee crashed\n"); + else if (!WIFEXITED(status)) + ksft_test_result_fail("Tracee stopped for an unexpected reason: %d\n", s= tatus); + else if (WEXITSTATUS(status) !=3D 0) + ksft_test_result_fail("Tracee reported failure\n"); + else + ksft_test_result_pass("Tracee exited correctly\n"); + + ksft_finished(); } --=20 2.39.2