From patchwork Fri Jul 12 08:53:16 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Muhammad Usama Anjum X-Patchwork-Id: 13731422 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 DD4341428EA; Fri, 12 Jul 2024 08:53:40 +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=1720774422; cv=none; b=m36j/pdQ6AKjcY3PTCUAz832+r2nwkSM4N4dIggDuK4SYJ/N7anK77bk5yCT9mcHROk8Azi8qiLkGkwz0+hSlli5UVoCkElot7nAM/TDCnJIfzoQ5VOnIlvjVzfVj4a5RTb2P7qFrNJzGrVfLWDG9+hX4WY6MuFDcsUaeFJTAcA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720774422; c=relaxed/simple; bh=3MDi7FHmO1ZC5BgTBljZuDhp6QNlf+5LjqAVlUaXsWE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Um5tyWReSlDXgHwipiYB0OW8MsFJAHdGrq2/HVOFWCGLvtoqZQUbaeu63+nA9YBK1K5HBswoPlY7WdlzH23iOHblERfMDgiNwGY+AVIVALfKNzcEW7A2TjL/usPAnZPTWzkh7ELnKANEMjoz0CGcYR8M6uUmA0YUmWgmc9WNq/I= 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=3KELC0Vw; 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="3KELC0Vw" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1720774419; bh=3MDi7FHmO1ZC5BgTBljZuDhp6QNlf+5LjqAVlUaXsWE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=3KELC0Vw1yS8iMMJ8L5phDAM16eCU/dZh1yJcSaDNmWbpDQt/V7pBichBY0Ux8EZV QXICycrTPorUggNji20jmCsqrmsuJqYUT87CPFZ3nL8bMDEQ6KZJHWTRbw39TwWGsY +kliezCF7XhUyMtDRe70kwy68sBVLK1IhYmnb0j6yGzWzIwHlFVjxs4jchECeq3DtN Z+px5bKhOJfsCXfd9l9ZQ/vgm1zNz8MOnwFcz2xS8Ha+r9ER+a8S6VC7E6g0A97vIS wTrileybFUYBscbQR5Y3qILiEZiwyuI3OLt5QcCQBit7LZ8ETImz90Odf1iVNiwevC bwlSYdswZdczA== 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 BD6B137821DB; Fri, 12 Jul 2024 08:53:36 +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 v3 3/4] selftests: x86: fsgsbase_restore: remove manual counting and increase maintainability Date: Fri, 12 Jul 2024 13:53:16 +0500 Message-Id: <20240712085318.315386-4-usama.anjum@collabora.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240712085318.315386-1-usama.anjum@collabora.com> References: <20240712085318.315386-1-usama.anjum@collabora.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 - 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" #define EXPECTED_VALUE 0x1337f00d @@ -45,18 +46,18 @@ */ unsigned int dereference_seg_base(void); -static void init_seg(void) +static int init_seg(void) { unsigned int *target = mmap( NULL, sizeof(unsigned int), PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_32BIT, -1, 0); if (target == MAP_FAILED) - err(1, "mmap"); + ksft_exit_fail_perror("mmap"); *target = EXPECTED_VALUE; - printf("\tsegment base address = 0x%lx\n", (unsigned long)target); + ksft_print_msg("segment base address = 0x%lx\n", (unsigned long)target); struct user_desc desc = { .entry_number = 0, @@ -70,7 +71,7 @@ static void init_seg(void) .useable = 0 }; if (syscall(SYS_modify_ldt, 1, &desc, sizeof(desc)) == 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)); if (ret != 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); unsigned short sel = (unsigned short)((desc.entry_number << 3) | 0x3); asm volatile ("mov %0, %" SEG :: "rm" (sel)); } + + return 0; } 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"); /* * Write a nonzero selector with base zero to the segment register. @@ -129,70 +132,72 @@ static void tracee_zap_segment(void) pid_t pid = getpid(), tid = syscall(SYS_gettid); - printf("\tTracee is going back to sleep\n"); + ksft_print_msg("Tracee is going back to sleep\n"); syscall(SYS_tgkill, pid, tid, SIGSTOP); /* Should not get here. */ - while (true) { - printf("[FAIL]\tTracee hit unreachable code\n"); - pause(); - } + ksft_exit_fail_msg("Tracee hit unreachable code\n"); } 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 = init_seg(); + if (ret) + return ret; unsigned int val = dereference_seg_base(); - if (val != EXPECTED_VALUE) { - printf("[FAIL]\tseg[0] == %x; should be %x\n", val, EXPECTED_VALUE); - return 1; - } - printf("[OK]\tThe segment points to the right place.\n"); + ksft_test_result(val == EXPECTED_VALUE, "The segment points to the right place.\n"); pid_t chld = fork(); if (chld < 0) - err(1, "fork"); + ksft_exit_fail_perror("fork"); if (chld == 0) { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0, 0); if (ptrace(PTRACE_TRACEME, 0, 0, 0) != 0) - err(1, "PTRACE_TRACEME"); + ksft_exit_fail_perror("PTRACE_TRACEME"); pid_t pid = getpid(), tid = syscall(SYS_gettid); - 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); - printf("\tTracee was resumed. Will re-check segment.\n"); + ksft_print_msg("Tracee was resumed. Will re-check segment.\n"); val = dereference_seg_base(); - if (val != EXPECTED_VALUE) { - printf("[FAIL]\tseg[0] == %x; should be %x\n", val, EXPECTED_VALUE); - exit(1); + + if (val == EXPECTED_VALUE) { + ksft_print_msg("The segment points to the right place.\n"); + return EXIT_SUCCESS; } - printf("[OK]\tThe segment points to the right place.\n"); - exit(0); + ksft_print_msg("seg[0] == %x; should be %x\n", val, EXPECTED_VALUE); + return EXIT_FAILURE; } int status; /* Wait for SIGSTOP. */ if (waitpid(chld, &status, 0) != chld || !WIFSTOPPED(status)) - err(1, "waitpid"); + ksft_exit_fail_perror("waitpid"); struct user_regs_struct regs; if (ptrace(PTRACE_GETREGS, chld, NULL, ®s) != 0) - err(1, "PTRACE_GETREGS"); + ksft_exit_fail_perror("PTRACE_GETREGS"); #ifdef __x86_64__ - printf("\tChild GS=0x%lx, GSBASE=0x%lx\n", (unsigned long)regs.gs, (unsigned long)regs.gs_base); + ksft_print_msg("Child GS=0x%lx, GSBASE=0x%lx\n", (unsigned long)regs.gs, (unsigned long)regs.gs_base); #else - printf("\tChild FS=0x%lx\n", (unsigned long)regs.xfs); + ksft_print_msg("Child FS=0x%lx\n", (unsigned long)regs.xfs); #endif struct user_regs_struct regs2 = regs; @@ -203,42 +208,34 @@ int main() regs2.eip = (unsigned long)tracee_zap_segment; #endif - 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) != 0) - err(1, "PTRACE_GETREGS"); + ksft_exit_fail_perror("PTRACE_GETREGS"); if (ptrace(PTRACE_CONT, chld, NULL, NULL) != 0) - err(1, "PTRACE_GETREGS"); + ksft_exit_fail_perror("PTRACE_GETREGS"); /* Wait for SIGSTOP. */ if (waitpid(chld, &status, 0) != chld || !WIFSTOPPED(status)) - err(1, "waitpid"); + ksft_exit_fail_perror("waitpid"); - printf("\tTracer: restoring tracee state\n"); + ksft_print_msg("Tracer: restoring tracee state\n"); if (ptrace(PTRACE_SETREGS, chld, NULL, ®s) != 0) - err(1, "PTRACE_GETREGS"); + ksft_exit_fail_perror("PTRACE_GETREGS"); if (ptrace(PTRACE_DETACH, chld, NULL, NULL) != 0) - err(1, "PTRACE_GETREGS"); + ksft_exit_fail_perror("PTRACE_GETREGS"); /* Wait for SIGSTOP. */ if (waitpid(chld, &status, 0) != 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 = WEXITSTATUS(status); - if (exitcode != 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", status); + else if (WEXITSTATUS(status) != 0) + ksft_test_result_fail("Tracee reported failure\n"); + else + ksft_test_result_pass("Tracee exited correctly\n"); + + ksft_finished(); }