From patchwork Tue Oct 29 23:17:47 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ilya Leoshkevich X-Patchwork-Id: 13855644 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BAFFAD7494D for ; Tue, 29 Oct 2024 23:23:13 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1t5vXc-0004D8-Sj; Tue, 29 Oct 2024 19:22:24 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1t5vXa-0004Cm-Lk for qemu-devel@nongnu.org; Tue, 29 Oct 2024 19:22:22 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1t5vXY-00045m-IO for qemu-devel@nongnu.org; Tue, 29 Oct 2024 19:22:22 -0400 Received: from pps.filterd (m0353725.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 49TLKBAI021909; Tue, 29 Oct 2024 23:22:18 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:date:from:in-reply-to:message-id :mime-version:references:subject:to; s=pp1; bh=elkOFMLAOG0QMfWUi cilS7TVTzCePyoAKqei98EDHBs=; b=XxXX/VHB3cIX0LMu4OTWmNqlKXnWRyfAN Dqygt/VYuOjsl+enKM08E/mHSv0VuZUr6O284OCLZ51RBtRDPKwcmSQODWYY4ror V3LtNpAYyvAjH6tGTsZ1t6xznFY4CQXyoixq/tPy3yG9FNPxEOXfbu+hPYj5y648 QnY9LYoeWzSlDDrMKNfp7EIzYGaSNhwZjh2aOcAyVHHMuKLeL2t2WlQXRYNJIyVd gvZBL601jg/JYDsvlJ7FNFt1q580t4S0cHWE99NLunMzCdfJ8AiZlkxpfSYnyMtO h2BZCccfzq+p/9TEB7C6xXKojufehIaOC/xv2II9wsLGg0d+FueNg== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 42jb65fkgu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 29 Oct 2024 23:22:17 +0000 (GMT) Received: from m0353725.ppops.net (m0353725.ppops.net [127.0.0.1]) by pps.reinject (8.18.0.8/8.18.0.8) with ESMTP id 49TNMHfj022873; Tue, 29 Oct 2024 23:22:17 GMT Received: from ppma23.wdc07v.mail.ibm.com (5d.69.3da9.ip4.static.sl-reverse.com [169.61.105.93]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 42jb65fkgt-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 29 Oct 2024 23:22:17 +0000 (GMT) Received: from pps.filterd (ppma23.wdc07v.mail.ibm.com [127.0.0.1]) by ppma23.wdc07v.mail.ibm.com (8.18.1.2/8.18.1.2) with ESMTP id 49TMSgFd018371; Tue, 29 Oct 2024 23:22:16 GMT Received: from smtprelay05.fra02v.mail.ibm.com ([9.218.2.225]) by ppma23.wdc07v.mail.ibm.com (PPS) with ESMTPS id 42hc8k5b4s-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 29 Oct 2024 23:22:16 +0000 Received: from smtpav04.fra02v.mail.ibm.com (smtpav04.fra02v.mail.ibm.com [10.20.54.103]) by smtprelay05.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 49TNMEwT54853930 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 29 Oct 2024 23:22:14 GMT Received: from smtpav04.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B7C8E20043; Tue, 29 Oct 2024 23:22:14 +0000 (GMT) Received: from smtpav04.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 544E720040; Tue, 29 Oct 2024 23:22:14 +0000 (GMT) Received: from heavy.ibm.com (unknown [9.171.12.2]) by smtpav04.fra02v.mail.ibm.com (Postfix) with ESMTP; Tue, 29 Oct 2024 23:22:14 +0000 (GMT) From: Ilya Leoshkevich To: Richard Henderson , =?utf-8?q?Philippe_Mat?= =?utf-8?q?hieu-Daud=C3=A9?= , =?utf-8?q?Alex_Benn=C3=A9e?= , Laurent Vivier Cc: qemu-devel@nongnu.org, Michael Tokarev , Brian Cain , "ltaylorsimpson @ gmail . com" , Ilya Leoshkevich Subject: [PATCH v3 1/2] linux-user: Allow custom rt signal mappings Date: Wed, 30 Oct 2024 00:17:47 +0100 Message-ID: <20241029232211.206766-2-iii@linux.ibm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241029232211.206766-1-iii@linux.ibm.com> References: <20241029232211.206766-1-iii@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: jRUBoJdGdfCHcRT9VMDDSuWladIW0PvE X-Proofpoint-GUID: DgWnHWaMTC2o9H9aquTNoYsLrfwyEJGL X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1051,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-10-15_01,2024-10-11_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 clxscore=1015 adultscore=0 phishscore=0 bulkscore=0 mlxlogscore=999 impostorscore=0 spamscore=0 suspectscore=0 mlxscore=0 malwarescore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2409260000 definitions=main-2410290175 Received-SPF: pass client-ip=148.163.158.5; envelope-from=iii@linux.ibm.com; helo=mx0b-001b2d01.pphosted.com X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Some applications want to use low priority realtime signals (e.g., SIGRTMAX). Currently QEMU cannot map all target realtime signals to host realtime signals, and chooses to sacrifice the end of the target realtime signal range. Allow users to choose how to map target realtime signals to host realtime signals using the new -t option, the new QEMU_RTSIG_MAP environment variable, and the new -Drtsig_map=\"...\" meson flag. To simplify things, the meson flag is not per-target, because the intended use case is app-specific qemu-user builds. The mapping is specified using the "tsig hsig count[,...]" syntax. Target realtime signals [tsig,tsig+count) are mapped to host realtime signals [hsig,hsig+count). Care is taken to avoid double and out-of-range mappings. Signed-off-by: Ilya Leoshkevich Reviewed-by: Richard Henderson --- linux-user/main.c | 12 +++- linux-user/signal-common.h | 2 +- linux-user/signal.c | 108 +++++++++++++++++++++++++++------- meson.build | 3 +- meson_options.txt | 2 + scripts/meson-buildoptions.sh | 2 + 6 files changed, 106 insertions(+), 23 deletions(-) diff --git a/linux-user/main.c b/linux-user/main.c index 8143a0d4b02..b09af8d4365 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -412,6 +412,13 @@ static void handle_arg_reserved_va(const char *arg) reserved_va = val ? val - 1 : 0; } +static const char *rtsig_map = CONFIG_QEMU_RTSIG_MAP; + +static void handle_arg_rtsig_map(const char *arg) +{ + rtsig_map = arg; +} + static void handle_arg_one_insn_per_tb(const char *arg) { opt_one_insn_per_tb = true; @@ -494,6 +501,9 @@ static const struct qemu_argument arg_table[] = { "address", "set guest_base address to 'address'"}, {"R", "QEMU_RESERVED_VA", true, handle_arg_reserved_va, "size", "reserve 'size' bytes for guest virtual address space"}, + {"t", "QEMU_RTSIG_MAP", true, handle_arg_rtsig_map, + "tsig hsig n[,...]", + "map target rt signals [tsig,tsig+n) to [hsig,hsig+n]"}, {"d", "QEMU_LOG", true, handle_arg_log, "item[,...]", "enable logging of specified items " "(use '-d help' for a list of items)"}, @@ -1002,7 +1012,7 @@ int main(int argc, char **argv, char **envp) target_set_brk(info->brk); syscall_init(); - signal_init(); + signal_init(rtsig_map); /* Now that we've loaded the binary, GUEST_BASE is fixed. Delay generating the prologue until now so that the prologue can take diff --git a/linux-user/signal-common.h b/linux-user/signal-common.h index f4cbe6185e1..8584d9ecc2a 100644 --- a/linux-user/signal-common.h +++ b/linux-user/signal-common.h @@ -56,7 +56,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, target_sigset_t *set, CPUArchState *env); void process_pending_signals(CPUArchState *cpu_env); -void signal_init(void); +void signal_init(const char *rtsig_map); void queue_signal(CPUArchState *env, int sig, int si_type, target_siginfo_t *info); void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info); diff --git a/linux-user/signal.c b/linux-user/signal.c index 63ac2df53b7..9b6d772882d 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -18,6 +18,7 @@ */ #include "qemu/osdep.h" #include "qemu/bitops.h" +#include "qemu/cutils.h" #include "gdbstub/user.h" #include "exec/page-protection.h" #include "hw/core/tcg-cpu-ops.h" @@ -513,20 +514,81 @@ static int core_dump_signal(int sig) } } -static void signal_table_init(void) +static void signal_table_init(const char *rtsig_map) { int hsig, tsig, count; + if (rtsig_map) { + /* + * Map host RT signals to target RT signals according to the + * user-provided specification. + */ + const char *s = rtsig_map; + + while (true) { + int i; + + if (qemu_strtoi(s, &s, 10, &tsig) || *s++ != ' ') { + fprintf(stderr, "Malformed target signal in QEMU_RTSIG_MAP\n"); + exit(EXIT_FAILURE); + } + if (qemu_strtoi(s, &s, 10, &hsig) || *s++ != ' ') { + fprintf(stderr, "Malformed host signal in QEMU_RTSIG_MAP\n"); + exit(EXIT_FAILURE); + } + if (qemu_strtoi(s, &s, 10, &count) || (*s && *s != ',')) { + fprintf(stderr, "Malformed signal count in QEMU_RTSIG_MAP\n"); + exit(EXIT_FAILURE); + } + + for (i = 0; i < count; i++, tsig++, hsig++) { + if (tsig < TARGET_SIGRTMIN || tsig > TARGET_NSIG) { + fprintf(stderr, "%d is not a target rt signal\n", tsig); + exit(EXIT_FAILURE); + } + if (hsig < SIGRTMIN || hsig > SIGRTMAX) { + fprintf(stderr, "%d is not a host rt signal\n", hsig); + exit(EXIT_FAILURE); + } + if (host_to_target_signal_table[hsig]) { + fprintf(stderr, "%d already maps %d\n", + hsig, host_to_target_signal_table[hsig]); + exit(EXIT_FAILURE); + } + host_to_target_signal_table[hsig] = tsig; + } + + if (*s) { + s++; + } else { + break; + } + } + } else { + /* + * Default host-to-target RT signal mapping. + * + * Signals are supported starting from TARGET_SIGRTMIN and going up + * until we run out of host realtime signals. Glibc uses the lower 2 + * RT signals and (hopefully) nobody uses the upper ones. + * This is why SIGRTMIN (34) is generally greater than __SIGRTMIN (32). + * To fix this properly we would need to do manual signal delivery + * multiplexed over a single host signal. + * Attempts for configure "missing" signals via sigaction will be + * silently ignored. + * + * Reserve one signal for internal usage (see below). + */ + + hsig = SIGRTMIN + 1; + for (tsig = TARGET_SIGRTMIN; + hsig <= SIGRTMAX && tsig <= TARGET_NSIG; + hsig++, tsig++) { + host_to_target_signal_table[hsig] = tsig; + } + } + /* - * Signals are supported starting from TARGET_SIGRTMIN and going up - * until we run out of host realtime signals. Glibc uses the lower 2 - * RT signals and (hopefully) nobody uses the upper ones. - * This is why SIGRTMIN (34) is generally greater than __SIGRTMIN (32). - * To fix this properly we would need to do manual signal delivery - * multiplexed over a single host signal. - * Attempts for configure "missing" signals via sigaction will be - * silently ignored. - * * Remap the target SIGABRT, so that we can distinguish host abort * from guest abort. When the guest registers a signal handler or * calls raise(SIGABRT), the host will raise SIG_RTn. If the guest @@ -536,21 +598,27 @@ static void signal_table_init(void) * parent sees the correct mapping from wait status. */ - hsig = SIGRTMIN; host_to_target_signal_table[SIGABRT] = 0; - host_to_target_signal_table[hsig++] = TARGET_SIGABRT; - - for (tsig = TARGET_SIGRTMIN; - hsig <= SIGRTMAX && tsig <= TARGET_NSIG; - hsig++, tsig++) { - host_to_target_signal_table[hsig] = tsig; + for (hsig = SIGRTMIN; hsig <= SIGRTMAX; hsig++) { + if (!host_to_target_signal_table[hsig]) { + host_to_target_signal_table[hsig] = TARGET_SIGABRT; + break; + } + } + if (hsig > SIGRTMAX) { + fprintf(stderr, "No rt signals left for SIGABRT mapping\n"); + exit(EXIT_FAILURE); } /* Invert the mapping that has already been assigned. */ for (hsig = 1; hsig < _NSIG; hsig++) { tsig = host_to_target_signal_table[hsig]; if (tsig) { - assert(target_to_host_signal_table[tsig] == 0); + if (target_to_host_signal_table[tsig]) { + fprintf(stderr, "%d is already mapped to %d\n", + tsig, target_to_host_signal_table[tsig]); + exit(EXIT_FAILURE); + } target_to_host_signal_table[tsig] = hsig; } } @@ -573,13 +641,13 @@ static void signal_table_init(void) trace_signal_table_init(count); } -void signal_init(void) +void signal_init(const char *rtsig_map) { TaskState *ts = get_task_state(thread_cpu); struct sigaction act, oact; /* initialize signal conversion tables */ - signal_table_init(); + signal_table_init(rtsig_map); /* Set the signal mask from the host mask. */ sigprocmask(0, 0, &ts->signal_mask); diff --git a/meson.build b/meson.build index 85594fd3f18..bc282c8d187 100644 --- a/meson.build +++ b/meson.build @@ -3167,7 +3167,8 @@ foreach target : target_dirs config_target += { 'CONFIG_USER_ONLY': 'y', 'CONFIG_QEMU_INTERP_PREFIX': - get_option('interp_prefix').replace('%M', config_target['TARGET_NAME']) + get_option('interp_prefix').replace('%M', config_target['TARGET_NAME']), + 'CONFIG_QEMU_RTSIG_MAP': get_option('rtsig_map'), } endif diff --git a/meson_options.txt b/meson_options.txt index 0ee4d7bb86b..b61808b46a6 100644 --- a/meson_options.txt +++ b/meson_options.txt @@ -27,6 +27,8 @@ option('block_drv_ro_whitelist', type : 'string', value : '', description: 'set block driver read-only whitelist (by default affects only QEMU, not tools like qemu-img)') option('interp_prefix', type : 'string', value : '/usr/gnemul/qemu-%M', description: 'where to find shared libraries etc., use %M for cpu name') +option('rtsig_map', type : 'string', value : 'NULL', + description: 'default value of QEMU_RTSIG_MAP') option('fuzzing_engine', type : 'string', value : '', description: 'fuzzing engine library for OSS-Fuzz') option('trace_file', type: 'string', value: 'trace', diff --git a/scripts/meson-buildoptions.sh b/scripts/meson-buildoptions.sh index 6d08605b771..9684f82ffbb 100644 --- a/scripts/meson-buildoptions.sh +++ b/scripts/meson-buildoptions.sh @@ -72,6 +72,7 @@ meson_options_help() { printf "%s\n" ' "manufacturer" name for qemu-ga registry entries' printf "%s\n" ' [QEMU]' printf "%s\n" ' --qemu-ga-version=VALUE version number for qemu-ga installer' + printf "%s\n" ' --rtsig-map=VALUE default value of QEMU_RTSIG_MAP [NULL]' printf "%s\n" ' --smbd=VALUE Path to smbd for slirp networking' printf "%s\n" ' --sysconfdir=VALUE Sysconf data directory [etc]' printf "%s\n" ' --tls-priority=VALUE Default TLS protocol/cipher priority string' @@ -457,6 +458,7 @@ _meson_option_parse() { --disable-replication) printf "%s" -Dreplication=disabled ;; --enable-rng-none) printf "%s" -Drng_none=true ;; --disable-rng-none) printf "%s" -Drng_none=false ;; + --rtsig-map=*) quote_sh "-Drtsig_map=$2" ;; --enable-rust) printf "%s" -Drust=enabled ;; --disable-rust) printf "%s" -Drust=disabled ;; --enable-rutabaga-gfx) printf "%s" -Drutabaga_gfx=enabled ;;