From patchwork Wed Feb 12 12:56:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Laurent Vivier X-Patchwork-Id: 11378479 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 101DA13A4 for ; Wed, 12 Feb 2020 12:58:58 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id E386F20659 for ; Wed, 12 Feb 2020 12:58:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E386F20659 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=vivier.eu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:36976 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j1rbU-0000Y4-1V for patchwork-qemu-devel@patchwork.kernel.org; Wed, 12 Feb 2020 07:58:56 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:60878) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j1raZ-0007Zj-VI for qemu-devel@nongnu.org; Wed, 12 Feb 2020 07:58:20 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j1raP-0003s9-GZ for qemu-devel@nongnu.org; Wed, 12 Feb 2020 07:57:59 -0500 Received: from mout.kundenserver.de ([212.227.126.133]:51335) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1j1raP-0003rF-7G for qemu-devel@nongnu.org; Wed, 12 Feb 2020 07:57:49 -0500 Received: from localhost.localdomain ([78.238.229.36]) by mrelayeu.kundenserver.de (mreue009 [212.227.15.167]) with ESMTPSA (Nemesis) id 1MHoZS-1jFYQB4ATe-00EvBY; Wed, 12 Feb 2020 13:57:06 +0100 From: Laurent Vivier To: qemu-devel@nongnu.org Subject: [PATCH v3 4/4] linux-user: fix use of SIGRTMIN Date: Wed, 12 Feb 2020 13:56:58 +0100 Message-Id: <20200212125658.644558-5-laurent@vivier.eu> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200212125658.644558-1-laurent@vivier.eu> References: <20200212125658.644558-1-laurent@vivier.eu> MIME-Version: 1.0 X-Provags-ID: V03:K1:J92mwqrY8tMW58Fc7j+NPrHkaGX9N6Me3XwyeYxAeTcxENAHD3W CI1Gcj/g44tXy0DWFr1Hjfh4XWDRhascm4w2kXIPfB6T8golCLT4hjxnJSmZEyWmrpJGgBr 8Hu31rxW5TUR3x3rojmmn0W6h2P2Azsuc9T/lmNcsFy3dVUWv4l6Nh7LG7T2i/GW9XHI2AE juH/AB8QYcYn867AoqYrA== X-UI-Out-Filterresults: notjunk:1;V03:K0:DJQHfzKL2kQ=:CX1qI1f8d0asqplHJkHI0q akaZiY9Xc0WpZSZWQDsdTBXZxtoSty2QkpyswZuus4s1haqOHhAxGMnamtd/0MECQ7eUhtQG8 oSiEjWlNZmUlPWYRThJDCgkStlM+TkwqVBr1kxG6UHIvkOf/AImBRTlCuon47mCCALZgCGR6M WZXe3GcqvWfrE2tu5W5a++lhSnPpaU50SM9yqJu9Sy6AS5vZ8MCBccGaJ3DYbvJ866wfMw4Mn PPCZRr6SP7R2fbeH7yvlAd7m5RRFI8QlLJYpGEqLc+snuosnkbSzyvxNzvUrilqUiMsCB5Ila DgraK+tYn2SmyLu66pBxQ5vRGOCjSPPw0Jm3+DRee+0ztlc2AluW/pdqom491PPonC6yjki0S lMv5FEDzpyoUGMi37ob7LMc2G7JZewz59yfBNZuGAB0COYttf9sDjomtuJS0bWzkzNJXoJg3Y IN3Rxw14AbnGxHJSIpNZelnQhWrLDkojIB7x+zPcTFlN4bqpHmowevIDKFe3WQJh6StUZTbAA 762k1d8zie5M6+LNPuLuiAcZZLg/xdIG5LgJdcm3VGjWXTwDB5TNqRqmckgM/sgEPv7Xnh/TV cSAGediKkMFzfh2HUHRmY8JxRzWzOCic/cEncJprF3/jdfybinRNKBzG+P4i2mM5xifk12KEm b4JkySZcku2kOH1zGDL6O8qSh6E9fuZSlgHf36NqNZi2Vitv1r759cwj1NyYg17gGnZG+917A UsTT3v/JnefsBhcuSTACBoEUsOrYQa/jKh/ew2+H0RzMfVdAWSVn2HiNTMaiz/HYdJ/8dNBEa K8r/ACgCN4Vjx3wkvuJntw/ytiEudYALT4vInP7yecsVHrOZ5M+zQYObl4NltnPVcWo6ozf X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 212.227.126.133 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Maydell , Marlies Ruck , Riku Voipio , Laurent Vivier , Aleksandar Markovic , Josh Kunz , Taylor Simpson , Matus Kysel , milos.stojanovic@rt-rk.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" Some RT signals can be in use by glibc, it's why SIGRTMIN (34) is generally greater than __SIGRTMIN (32). So SIGRTMIN cannot be mapped to TARGET_SIGRTMIN. Instead of swapping only SIGRTMIN and SIGRTMAX, map all the range [TARGET_SIGRTMIN ... TARGET_SIGRTMAX - X] to [__SIGRTMIN + X ... SIGRTMAX ] (SIGRTMIN is __SIGRTMIN + X). Signed-off-by: Laurent Vivier Reviewed-by: Taylor Simson Reviewed-by: Peter Maydell --- Notes: v3: use trace_event_get_state_backends() update comments v2: ignore error when target sig <= TARGET_NSIG but host sig > SIGRTMAX replace i, j by target_sig, host_sig update signal_table_init() trace message linux-user/signal.c | 50 ++++++++++++++++++++++++++++++++++++----- linux-user/trace-events | 3 +++ 2 files changed, 48 insertions(+), 5 deletions(-) diff --git a/linux-user/signal.c b/linux-user/signal.c index c1e664f97a7c..046159dd0c5b 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -498,18 +498,30 @@ static int core_dump_signal(int sig) static void signal_table_init(void) { - int host_sig, target_sig; + int host_sig, target_sig, count; /* - * Nasty hack: Reverse SIGRTMIN and SIGRTMAX to avoid overlap with - * host libpthread signals. This assumes no one actually uses SIGRTMAX :-/ + * Signals are supported starting from TARGET_SIGRTMIN and going up + * until we run out of host realtime signals. + * glibc at least uses only the lower 2 rt signals and probably + * nobody's using the upper ones. + * it's why SIGRTMIN (34) is generally greater than __SIGRTMIN (32) * To fix this properly we need to do manual signal delivery multiplexed * over a single host signal. + * Attempts for configure "missing" signals via sigaction will be + * silently ignored. */ - host_to_target_signal_table[__SIGRTMIN] = __SIGRTMAX; - host_to_target_signal_table[__SIGRTMAX] = __SIGRTMIN; + for (host_sig = SIGRTMIN; host_sig <= SIGRTMAX; host_sig++) { + target_sig = host_sig - SIGRTMIN + TARGET_SIGRTMIN; + if (target_sig <= TARGET_NSIG) { + host_to_target_signal_table[host_sig] = target_sig; + } + } /* generate signal conversion tables */ + for (target_sig = 1; target_sig <= TARGET_NSIG; target_sig++) { + target_to_host_signal_table[target_sig] = _NSIG; /* poison */ + } for (host_sig = 1; host_sig < _NSIG; host_sig++) { if (host_to_target_signal_table[host_sig] == 0) { host_to_target_signal_table[host_sig] = host_sig; @@ -519,6 +531,15 @@ static void signal_table_init(void) target_to_host_signal_table[target_sig] = host_sig; } } + + if (trace_event_get_state_backends(TRACE_SIGNAL_TABLE_INIT)) { + for (target_sig = 1, count = 0; target_sig <= TARGET_NSIG; target_sig++) { + if (target_to_host_signal_table[target_sig] == _NSIG) { + count++; + } + } + trace_signal_table_init(count); + } } void signal_init(void) @@ -817,6 +838,8 @@ int do_sigaction(int sig, const struct target_sigaction *act, int host_sig; int ret = 0; + trace_signal_do_sigaction_guest(sig, TARGET_NSIG); + if (sig < 1 || sig > TARGET_NSIG || sig == TARGET_SIGKILL || sig == TARGET_SIGSTOP) { return -TARGET_EINVAL; } @@ -847,6 +870,23 @@ int do_sigaction(int sig, const struct target_sigaction *act, /* we update the host linux signal state */ host_sig = target_to_host_signal(sig); + trace_signal_do_sigaction_host(host_sig, TARGET_NSIG); + if (host_sig > SIGRTMAX) { + /* we don't have enough host signals to map all target signals */ + qemu_log_mask(LOG_UNIMP, "Unsupported target signal #%d, ignored\n", + sig); + /* + * we don't return an error here because some programs try to + * register an handler for all possible rt signals even if they + * don't need it. + * An error here can abort them whereas there can be no problem + * to not have the signal available later. + * This is the case for golang, + * See https://github.com/golang/go/issues/33746 + * So we silently ignore the error. + */ + return 0; + } if (host_sig != SIGSEGV && host_sig != SIGBUS) { sigfillset(&act1.sa_mask); act1.sa_flags = SA_SIGINFO; diff --git a/linux-user/trace-events b/linux-user/trace-events index f6de1b8befc0..0296133daeb6 100644 --- a/linux-user/trace-events +++ b/linux-user/trace-events @@ -1,6 +1,9 @@ # See docs/devel/tracing.txt for syntax documentation. # signal.c +signal_table_init(int i) "number of unavailable signals: %d" +signal_do_sigaction_guest(int sig, int max) "target signal %d (MAX %d)" +signal_do_sigaction_host(int sig, int max) "host signal %d (MAX %d)" # */signal.c user_setup_frame(void *env, uint64_t frame_addr) "env=%p frame_addr=0x%"PRIx64 user_setup_rt_frame(void *env, uint64_t frame_addr) "env=%p frame_addr=0x%"PRIx64