{"id":835,"url":"http://patchwork.ozlabs.org/api/1.0/patches/835/?format=json","project":{"id":2,"url":"http://patchwork.ozlabs.org/api/1.0/projects/2/?format=json","name":"Linux PPC development","link_name":"linuxppc-dev","list_id":"linuxppc-dev.lists.ozlabs.org","list_email":"linuxppc-dev@lists.ozlabs.org","web_url":"https://github.com/linuxppc/wiki/wiki","scm_url":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git","webscm_url":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/"},"msgid":"<200809221602.32616.srinivasa@in.ibm.com>","date":"2008-09-22T10:32:32","name":"[RFC] Demultiplexing SIGTRAP signal","commit_ref":null,"pull_url":null,"state":"rfc","archived":true,"hash":"be5c41b86405a4e802b897028264642f6a5b050a","submitter":{"id":390,"url":"http://patchwork.ozlabs.org/api/1.0/people/390/?format=json","name":"Srinivasa Ds","email":"srinivasa@in.ibm.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/linuxppc-dev/patch/200809221602.32616.srinivasa@in.ibm.com/mbox/","series":[],"check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/835/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":["patchwork-incoming@ozlabs.org","linuxppc-dev@ozlabs.org"],"Delivered-To":["patchwork-incoming@ozlabs.org","linuxppc-dev@ozlabs.org"],"Received":["from ozlabs.org (localhost [127.0.0.1])\n\tby ozlabs.org (Postfix) with ESMTP id CDBC0DE071\n\tfor ;\n\tMon, 22 Sep 2008 20:32:27 +1000 (EST)","from e28esmtp06.in.ibm.com (e28smtp06.in.ibm.com [59.145.155.6])\n\t(using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits))\n\t(Client CN \"e28smtp06.in.ibm.com\", Issuer \"Equifax\" (verified OK))\n\tby ozlabs.org (Postfix) with ESMTPS id E97D1DDF17\n\tfor ; Mon, 22 Sep 2008 20:32:13 +1000 (EST)","from d28relay02.in.ibm.com (d28relay02.in.ibm.com [9.184.220.59])\n\tby e28esmtp06.in.ibm.com (8.13.1/8.13.1) with ESMTP id\n\tm8MAVwQm004126\n\tfor ; Mon, 22 Sep 2008 16:01:58 +0530","from d28av01.in.ibm.com (d28av01.in.ibm.com [9.184.220.63])\n\tby d28relay02.in.ibm.com (8.13.8/8.13.8/NCO v9.1) with ESMTP id\n\tm8MAVwbf1695862\n\tfor ; Mon, 22 Sep 2008 16:01:58 +0530","from d28av01.in.ibm.com (loopback [127.0.0.1])\n\tby d28av01.in.ibm.com (8.13.1/8.13.3) with ESMTP id m8MAVvGm010622\n\tfor ; Mon, 22 Sep 2008 16:01:58 +0530","from srinivasa-009124031087.in.ibm.com ([9.124.31.87])\n\tby d28av01.in.ibm.com (8.13.1/8.12.11) with ESMTP id m8MAVvAW009779; \n\tMon, 22 Sep 2008 16:01:57 +0530"],"From":"Srinivasa Ds ","Organization":"IBM","To":"linux-kernel@vger.kernel.org, akpm@linux-foundation.org, paulus@samba.org,\n\troland@redhat.com, linuxppc-dev@ozlabs.org, mingo@elte.hu,\n\tlinux-parisc@vger.kernel.org","Subject":"[RFC][PATCH] Demultiplexing SIGTRAP signal","Date":"Mon, 22 Sep 2008 16:02:32 +0530","User-Agent":"KMail/1.9.9","MIME-Version":"1.0","Content-Disposition":"inline","Message-Id":"<200809221602.32616.srinivasa@in.ibm.com>","X-BeenThere":"linuxppc-dev@ozlabs.org","X-Mailman-Version":"2.1.11","Precedence":"list","List-Id":"Linux on PowerPC Developers Mail List ","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Content-Type":"text/plain; charset=\"us-ascii\"","Content-Transfer-Encoding":"7bit","Sender":"linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@ozlabs.org","Errors-To":"linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@ozlabs.org"},"content":"Currently a SIGTRAP signal can denote any one of below reasons.\n\t- Breakpoint hit\n\t- H/W debug register hit\n\t- Single step\n\t- SIGTRAP signal sent through kill() or rasie()\n\nArchitectures like powerpc/parisc provides infrastructure to demultiplex\nSIGTRAP signal by passing down the information for receiving SIGTRAP through\nsi_code of siginfot_t structure. Here is an attempt is generalise this \ninfrastructure by extending it to x86 and x86_64 archs. \n\nSigned-off-by: Srinivasa DS \n\n\n\n---\n arch/ia64/include/asm/siginfo.h | 5 -----\n arch/powerpc/include/asm/siginfo.h | 5 -----\n arch/x86/kernel/traps_32.c | 19 +++++++++++++++++--\n arch/x86/kernel/traps_64.c | 7 ++++++-\n include/asm-generic/siginfo.h | 2 ++\n include/asm-parisc/siginfo.h | 5 -----\n 6 files changed, 25 insertions(+), 18 deletions(-)","diff":"Index: linux-2.6.27-rc7/arch/ia64/include/asm/siginfo.h\n===================================================================\n--- linux-2.6.27-rc7.orig/arch/ia64/include/asm/siginfo.h\n+++ linux-2.6.27-rc7/arch/ia64/include/asm/siginfo.h\n@@ -113,11 +113,6 @@ typedef struct siginfo {\n #undef NSIGSEGV\n #define NSIGSEGV\t3\n \n-/*\n- * SIGTRAP si_codes\n- */\n-#define TRAP_BRANCH\t(__SI_FAULT|3)\t/* process taken branch trap */\n-#define TRAP_HWBKPT\t(__SI_FAULT|4)\t/* hardware breakpoint or watchpoint */\n #undef NSIGTRAP\n #define NSIGTRAP\t4\n \nIndex: linux-2.6.27-rc7/arch/powerpc/include/asm/siginfo.h\n===================================================================\n--- linux-2.6.27-rc7.orig/arch/powerpc/include/asm/siginfo.h\n+++ linux-2.6.27-rc7/arch/powerpc/include/asm/siginfo.h\n@@ -15,11 +15,6 @@\n \n #include \n \n-/*\n- * SIGTRAP si_codes\n- */\n-#define TRAP_BRANCH\t(__SI_FAULT|3)\t/* process taken branch trap */\n-#define TRAP_HWBKPT\t(__SI_FAULT|4)\t/* hardware breakpoint or watchpoint */\n #undef NSIGTRAP\n #define NSIGTRAP\t4\n \nIndex: linux-2.6.27-rc7/arch/x86/kernel/traps_32.c\n===================================================================\n--- linux-2.6.27-rc7.orig/arch/x86/kernel/traps_32.c\n+++ linux-2.6.27-rc7/arch/x86/kernel/traps_32.c\n@@ -890,6 +890,7 @@ void __kprobes do_int3(struct pt_regs *r\n void __kprobes do_debug(struct pt_regs *regs, long error_code)\n {\n \tstruct task_struct *tsk = current;\n+\tstruct siginfo info;\n \tunsigned int condition;\n \n \ttrace_hardirqs_fixup();\n@@ -935,8 +936,22 @@ void __kprobes do_debug(struct pt_regs *\n \t\t\tgoto clear_TF_reenable;\n \t}\n \n-\t/* Ok, finally something we can handle */\n-\tsend_sigtrap(tsk, regs, error_code);\n+\ttsk->thread.trap_no = 1;\n+\ttsk->thread.error_code = error_code;\n+\n+\tmemset(&info, 0, sizeof(info));\n+\tinfo.si_signo = SIGTRAP;\n+\tif (condition & DR_STEP)\n+\t\tinfo.si_code = TRAP_TRACE;\n+\telse if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3))\n+\t\tinfo.si_code = TRAP_HWBKPT;\n+\telse\n+\t\tinfo.si_code = TRAP_BRKPT;\n+\t/* User-mode ip? */\n+\tinfo.si_addr = user_mode_vm(regs) ? (void __user *) regs->ip : NULL;\n+\n+\t/* Send us the fake SIGTRAP */\n+\tforce_sig_info(SIGTRAP, &info, tsk);\n \n \t/*\n \t * Disable additional traps. They'll be re-enabled when\nIndex: linux-2.6.27-rc7/arch/x86/kernel/traps_64.c\n===================================================================\n--- linux-2.6.27-rc7.orig/arch/x86/kernel/traps_64.c\n+++ linux-2.6.27-rc7/arch/x86/kernel/traps_64.c\n@@ -936,7 +936,12 @@ asmlinkage void __kprobes do_debug(struc\n \ttsk->thread.error_code = error_code;\n \tinfo.si_signo = SIGTRAP;\n \tinfo.si_errno = 0;\n-\tinfo.si_code = TRAP_BRKPT;\n+\tif (condition & DR_STEP)\n+\t\tinfo.si_code = TRAP_TRACE;\n+\telse if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3))\n+\t\tinfo.si_code = TRAP_HWBKPT;\n+\telse\n+\t\tinfo.si_code = TRAP_BRKPT;\n \tinfo.si_addr = user_mode(regs) ? (void __user *)regs->ip : NULL;\n \tforce_sig_info(SIGTRAP, &info, tsk);\n \nIndex: linux-2.6.27-rc7/include/asm-generic/siginfo.h\n===================================================================\n--- linux-2.6.27-rc7.orig/include/asm-generic/siginfo.h\n+++ linux-2.6.27-rc7/include/asm-generic/siginfo.h\n@@ -199,6 +199,8 @@ typedef struct siginfo {\n */\n #define TRAP_BRKPT\t(__SI_FAULT|1)\t/* process breakpoint */\n #define TRAP_TRACE\t(__SI_FAULT|2)\t/* process trace trap */\n+#define TRAP_BRANCH (__SI_FAULT|3) /* process taken branch trap */\n+#define TRAP_HWBKPT (__SI_FAULT|4) /* hardware breakpoint or watchpoint \n*/\n #define NSIGTRAP\t2\n \n /*\nIndex: linux-2.6.27-rc7/include/asm-parisc/siginfo.h\n===================================================================\n--- linux-2.6.27-rc7.orig/include/asm-parisc/siginfo.h\n+++ linux-2.6.27-rc7/include/asm-parisc/siginfo.h\n@@ -3,11 +3,6 @@\n \n #include \n \n-/*\n- * SIGTRAP si_codes\n- */\n-#define TRAP_BRANCH\t(__SI_FAULT|3)\t/* process taken branch trap */\n-#define TRAP_HWBKPT\t(__SI_FAULT|4)\t/* hardware breakpoint or watchpoint */\n #undef NSIGTRAP\n #define NSIGTRAP\t4\n \n","prefixes":["RFC"]}