From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from s3.sipsolutions.net ([2a01:4f8:191:4433::2] helo=sipsolutions.net) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lHTqx-005UJG-2N for linux-um@lists.infradead.org; Wed, 03 Mar 2021 15:56:04 +0000 From: Benjamin Berg Subject: [PATCH 05/27] um: Make errors to stop ptraced child fatal during startup Date: Wed, 3 Mar 2021 16:55:01 +0100 Message-Id: <20210303155523.124277-6-benjamin@sipsolutions.net> In-Reply-To: <20210303155523.124277-1-benjamin@sipsolutions.net> References: <20210303155523.124277-1-benjamin@sipsolutions.net> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: linux-um@lists.infradead.org Cc: Benjamin Berg For the detection code to check whether SYSEMU_SINGLESTEP works correctly we needed some error cases while stopping to be non-fatal. However, at this point stop_ptraced_child must always succeed, and we can therefore simplify it slightly to exit immediately on error. Signed-off-by: Benjamin Berg --- arch/um/os-Linux/start_up.c | 41 +++++++++++-------------------------- 1 file changed, 12 insertions(+), 29 deletions(-) diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c index 4f8fbe51fad6..8e6f8c4f3f62 100644 --- a/arch/um/os-Linux/start_up.c +++ b/arch/um/os-Linux/start_up.c @@ -112,35 +112,20 @@ static int start_ptraced_child(void) return pid; } -/* When testing for SYSEMU support, if it is one of the broken versions, we - * must just avoid using sysemu, not panic, but only if SYSEMU features are - * broken. - * So only for SYSEMU features we test mustpanic, while normal host features - * must work anyway! - */ -static int stop_ptraced_child(int pid, int exitcode, int mustexit) +static void stop_ptraced_child(int pid, int exitcode) { - int status, n, ret = 0; + int status, n; + + if (ptrace(PTRACE_CONT, pid, 0, 0) < 0) + fatal_perror("stop_ptraced_child : ptrace failed"); - if (ptrace(PTRACE_CONT, pid, 0, 0) < 0) { - perror("stop_ptraced_child : ptrace failed"); - return -1; - } CATCH_EINTR(n = waitpid(pid, &status, 0)); if (!WIFEXITED(status) || (WEXITSTATUS(status) != exitcode)) { int exit_with = WEXITSTATUS(status); - if (exit_with == 2) - non_fatal("check_ptrace : child exited with status 2. " - "\nDisabling SYSEMU support.\n"); - non_fatal("check_ptrace : child exited with exitcode %d, while " - "expecting %d; status 0x%x\n", exit_with, - exitcode, status); - if (mustexit) - exit(1); - ret = -1; + fatal("stop_ptraced_child : child exited with exitcode %d, " + "while expecting %d; status 0x%x\n", exit_with, + exitcode, status); } - - return ret; } static void __init check_sysemu(void) @@ -185,16 +170,14 @@ static void __init check_sysemu(void) goto fail; } } - if (stop_ptraced_child(pid, 0, 0) < 0) - goto fail_stopped; + stop_ptraced_child(pid, 0); os_info("OK\n"); return; fail: - stop_ptraced_child(pid, 1, 0); -fail_stopped: + stop_ptraced_child(pid, 1); fatal("missing\n"); } @@ -233,7 +216,7 @@ static void __init check_ptrace(void) break; } } - stop_ptraced_child(pid, 0, 1); + stop_ptraced_child(pid, 0); os_info("OK\n"); check_sysemu(); } @@ -280,7 +263,7 @@ void __init os_early_checks(void) pid = start_ptraced_child(); if (init_registers(pid)) fatal("Failed to initialize default registers"); - stop_ptraced_child(pid, 1, 1); + stop_ptraced_child(pid, 1); } int __init parse_iomem(char *str, int *add) -- 2.29.2 _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um