From: Glenn Washburn <development@efficientek.com> To: Jan Kiszka <jan.kiszka@siemens.com>, Kieran Bingham <kbingham@kernel.org> Cc: Glenn Washburn <development@efficientek.com>, linux-um <linux-um@lists.infradead.org>, Richard Weinberger <richard@nod.at>, Johannes Berg <johannes@sipsolutions.net>, Anton Ivanov <anton.ivanov@kot-begemot.co.uk> Subject: [PATCH v2 0/2] GDB: Support getting current task struct in UML Date: Thu, 16 Feb 2023 01:37:17 -0600 [thread overview] Message-ID: <cover.1676532759.git.development@efficientek.com> (raw) Added suggestions from Jan. Glenn Glenn Washburn (2): scripts/gdb: Correct indentation in get_current_task scripts/gdb: Support getting current task struct in UML scripts/gdb/linux/cpus.py | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) Range-diff against v1: 1: f33ebe524590 ! 1: c5a916e094d9 scripts/gdb: Correct indentation in get_current_task @@ Commit message There is an extra space in a couple blocks in get_current_task. Though python does not care, let's make the spacing consistent. + Also, format better an if expression, removing unneeded parenthesis. ## scripts/gdb/linux/cpus.py ## @@ scripts/gdb/linux/cpus.py: def get_current_task(cpu): @@ scripts/gdb/linux/cpus.py: def get_current_task(cpu): - raise gdb.GdbError("Sorry, obtaining the current task is not allowed " - "while running in userspace(EL0)") + current_task_addr = gdb.parse_and_eval("$SP_EL0") -+ if((current_task_addr >> 63) != 0): ++ if (current_task_addr >> 63) != 0: + current_task = current_task_addr.cast(task_ptr_type) + return current_task.dereference() + else: 2: 8c3db2291f58 ! 2: 683d10e752cd scripts/gdb: Support getting current task struct in UML @@ Commit message A running x86 UML kernel reports with architecture "i386:x86-64" as it is a sub-architecture. However, a difference with bare-metal x86 kernels is in how it manages tasks and the current task struct. To - identify that the inferior is a UML kernel and not bare-metal, the - symbol "uml_kmalloc" is checked for. If it exists, then do the UML - specific way of getting the current task struct. + identify that the inferior is a UML kernel and not bare-metal, check + for the existence of the UML specific symbol "cpu_tasks" which + contains the current task struct. ## scripts/gdb/linux/cpus.py ## @@ scripts/gdb/linux/cpus.py: def get_current_task(cpu): @@ scripts/gdb/linux/cpus.py: def get_current_task(cpu): if utils.is_target_arch("x86"): - var_ptr = gdb.parse_and_eval("¤t_task") - return per_cpu(var_ptr, cpu).dereference() -+ if gdb.lookup_global_symbol("uml_kmalloc"): ++ if gdb.lookup_global_symbol("cpu_tasks"): ++ # This is a UML kernel, which stores the current task ++ # differently than other x86 sub architectures + var_ptr = gdb.parse_and_eval("(struct task_struct *)cpu_tasks[0].task") + return var_ptr.dereference() + else: @@ scripts/gdb/linux/cpus.py: def get_current_task(cpu): + return per_cpu(var_ptr, cpu).dereference() elif utils.is_target_arch("aarch64"): current_task_addr = gdb.parse_and_eval("$SP_EL0") - if((current_task_addr >> 63) != 0): + if (current_task_addr >> 63) != 0: -- 2.30.2 _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um
WARNING: multiple messages have this Message-ID (diff)
From: Glenn Washburn <development@efficientek.com> To: Jan Kiszka <jan.kiszka@siemens.com>, Kieran Bingham <kbingham@kernel.org> Cc: linux-kernel@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>, Glenn Washburn <development@efficientek.com>, linux-um <linux-um@lists.infradead.org>, Richard Weinberger <richard@nod.at>, Johannes Berg <johannes@sipsolutions.net>, Anton Ivanov <anton.ivanov@kot-begemot.co.uk> Subject: [PATCH v2 0/2] GDB: Support getting current task struct in UML Date: Fri, 17 Feb 2023 19:11:52 -0600 [thread overview] Message-ID: <cover.1676532759.git.development@efficientek.com> (raw) Message-ID: <20230218011152.WEF5PeMDNoVdyEsniCYyPim9uLro8tpaus3z69hqCSk@z> (raw) Added suggestions from Jan. Glenn Glenn Washburn (2): scripts/gdb: Correct indentation in get_current_task scripts/gdb: Support getting current task struct in UML scripts/gdb/linux/cpus.py | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) Range-diff against v1: 1: f33ebe524590 ! 1: c5a916e094d9 scripts/gdb: Correct indentation in get_current_task @@ Commit message There is an extra space in a couple blocks in get_current_task. Though python does not care, let's make the spacing consistent. + Also, format better an if expression, removing unneeded parenthesis. ## scripts/gdb/linux/cpus.py ## @@ scripts/gdb/linux/cpus.py: def get_current_task(cpu): @@ scripts/gdb/linux/cpus.py: def get_current_task(cpu): - raise gdb.GdbError("Sorry, obtaining the current task is not allowed " - "while running in userspace(EL0)") + current_task_addr = gdb.parse_and_eval("$SP_EL0") -+ if((current_task_addr >> 63) != 0): ++ if (current_task_addr >> 63) != 0: + current_task = current_task_addr.cast(task_ptr_type) + return current_task.dereference() + else: 2: 8c3db2291f58 ! 2: 683d10e752cd scripts/gdb: Support getting current task struct in UML @@ Commit message A running x86 UML kernel reports with architecture "i386:x86-64" as it is a sub-architecture. However, a difference with bare-metal x86 kernels is in how it manages tasks and the current task struct. To - identify that the inferior is a UML kernel and not bare-metal, the - symbol "uml_kmalloc" is checked for. If it exists, then do the UML - specific way of getting the current task struct. + identify that the inferior is a UML kernel and not bare-metal, check + for the existence of the UML specific symbol "cpu_tasks" which + contains the current task struct. ## scripts/gdb/linux/cpus.py ## @@ scripts/gdb/linux/cpus.py: def get_current_task(cpu): @@ scripts/gdb/linux/cpus.py: def get_current_task(cpu): if utils.is_target_arch("x86"): - var_ptr = gdb.parse_and_eval("¤t_task") - return per_cpu(var_ptr, cpu).dereference() -+ if gdb.lookup_global_symbol("uml_kmalloc"): ++ if gdb.lookup_global_symbol("cpu_tasks"): ++ # This is a UML kernel, which stores the current task ++ # differently than other x86 sub architectures + var_ptr = gdb.parse_and_eval("(struct task_struct *)cpu_tasks[0].task") + return var_ptr.dereference() + else: @@ scripts/gdb/linux/cpus.py: def get_current_task(cpu): + return per_cpu(var_ptr, cpu).dereference() elif utils.is_target_arch("aarch64"): current_task_addr = gdb.parse_and_eval("$SP_EL0") - if((current_task_addr >> 63) != 0): + if (current_task_addr >> 63) != 0: -- 2.30.2 _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um
next reply other threads:[~2023-02-16 7:37 UTC|newest] Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top 2023-02-16 7:37 Glenn Washburn [this message] 2023-02-16 7:37 ` [PATCH v2 1/2] scripts/gdb: Correct indentation in get_current_task Glenn Washburn 2023-02-18 1:11 ` Glenn Washburn 2023-02-16 7:37 ` [PATCH v2 2/2] scripts/gdb: Support getting current task struct in UML Glenn Washburn 2023-02-18 1:11 ` Glenn Washburn 2023-02-16 7:51 ` [PATCH v2 0/2] GDB: " Jan Kiszka 2023-02-16 22:40 ` Andrew Morton 2023-02-16 22:54 ` Richard Weinberger 2023-02-16 23:33 ` Andrew Morton 2023-02-17 10:14 ` Geert Uytterhoeven 2023-02-17 21:56 ` Glenn Washburn 2023-02-17 22:21 ` Andrew Morton 2023-02-18 1:11 ` Glenn Washburn 2023-02-23 21:14 ` Andrew Morton 2023-02-26 6:47 ` Glenn Washburn 2023-02-26 19:35 ` Andrew Morton
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