From mboxrd@z Thu Jan 1 00:00:00 1970 From: akpm@linux-foundation.org Subject: [merged] arm-add-loglvl-to-dump_backtrace.patch removed from -mm tree Date: Tue, 09 Jun 2020 17:37:07 -0700 Message-ID: <20200610003707.Oc05cms_W%akpm@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:39316 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726021AbgFJAhI (ORCPT ); Tue, 9 Jun 2020 20:37:08 -0400 Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: dima@arista.com, linux@armlinux.org.uk, mm-commits@vger.kernel.org, will@kernel.org The patch titled Subject: arm: add loglvl to dump_backtrace() has been removed from the -mm tree. Its filename was arm-add-loglvl-to-dump_backtrace.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Dmitry Safonov Subject: arm: add loglvl to dump_backtrace() Currently, the log-level of show_stack() depends on a platform realization. It creates situations where the headers are printed with lower log level or higher than the stacktrace (depending on a platform or user). Furthermore, it forces the logic decision from user to an architecture side. In result, some users as sysrq/kdb/etc are doing tricks with temporary rising console_loglevel while printing their messages. And in result it not only may print unwanted messages from other CPUs, but also omit printing at all in the unlucky case where the printk() was deferred. Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier approach than introducing more printk buffers. Also, it will consolidate printings with headers. Add log level argument to dump_backtrace() as a preparation for introducing show_stack_loglvl(). As a good side-effect __die() now prints not only "Stack:" header with KERN_EMERG, but the backtrace itself. [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Link: http://lkml.kernel.org/r/20200418201944.482088-7-dima@arista.com Signed-off-by: Dmitry Safonov Cc: Russell King Cc: Will Deacon Signed-off-by: Andrew Morton --- arch/arm/kernel/traps.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) --- a/arch/arm/kernel/traps.c~arm-add-loglvl-to-dump_backtrace +++ a/arch/arm/kernel/traps.c @@ -202,17 +202,19 @@ static void dump_instr(const char *lvl, } #ifdef CONFIG_ARM_UNWIND -static inline void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) +static inline void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, + const char *loglvl) { - unwind_backtrace(regs, tsk, KERN_DEFAULT); + unwind_backtrace(regs, tsk, loglvl); } #else -static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) +static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, + const char *loglvl) { unsigned int fp, mode; int ok = 1; - printk("Backtrace: "); + printk("%sBacktrace: ", loglvl); if (!tsk) tsk = current; @@ -239,13 +241,13 @@ static void dump_backtrace(struct pt_reg pr_cont("\n"); if (ok) - c_backtrace(fp, mode, NULL); + c_backtrace(fp, mode, loglvl); } #endif void show_stack(struct task_struct *tsk, unsigned long *sp) { - dump_backtrace(NULL, tsk); + dump_backtrace(NULL, tsk, KERN_DEFAULT); barrier(); } @@ -289,7 +291,7 @@ static int __die(const char *str, int er if (!user_mode(regs) || in_interrupt()) { dump_mem(KERN_EMERG, "Stack: ", regs->ARM_sp, THREAD_SIZE + (unsigned long)task_stack_page(tsk)); - dump_backtrace(regs, tsk); + dump_backtrace(regs, tsk, KERN_EMERG); dump_instr(KERN_EMERG, regs); } _ Patches currently in -mm which might be from dima@arista.com are