From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: [patch 29/93] sh: add loglvl to dump_mem() Date: Mon, 08 Jun 2020 21:31:24 -0700 Message-ID: <20200609043124.Q4pBi7KZY%akpm@linux-foundation.org> References: <20200608212922.5b7fa74ca3f4e2444441b7f9@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:54328 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725770AbgFIEb0 (ORCPT ); Tue, 9 Jun 2020 00:31:26 -0400 In-Reply-To: <20200608212922.5b7fa74ca3f4e2444441b7f9@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: akpm@linux-foundation.org, dalias@libc.org, dima@arista.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, ysato@users.sourceforge.jp From: Dmitry Safonov Subject: sh: add loglvl to dump_mem() 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_mem() as a preparation to introduce show_stack_loglvl(). [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Link: http://lkml.kernel.org/r/20200418201944.482088-30-dima@arista.com Signed-off-by: Dmitry Safonov Cc: Rich Felker Cc: Yoshinori Sato Signed-off-by: Andrew Morton --- arch/sh/include/asm/kdebug.h | 3 ++- arch/sh/kernel/dumpstack.c | 17 +++++++++-------- arch/sh/kernel/traps.c | 4 ++-- 3 files changed, 13 insertions(+), 11 deletions(-) --- a/arch/sh/include/asm/kdebug.h~sh-add-loglvl-to-dump_mem +++ a/arch/sh/include/asm/kdebug.h @@ -13,6 +13,7 @@ enum die_val { /* arch/sh/kernel/dumpstack.c */ extern void printk_address(unsigned long address, int reliable); -extern void dump_mem(const char *str, unsigned long bottom, unsigned long top); +extern void dump_mem(const char *str, const char *loglvl, + unsigned long bottom, unsigned long top); #endif /* __ASM_SH_KDEBUG_H */ --- a/arch/sh/kernel/dumpstack.c~sh-add-loglvl-to-dump_mem +++ a/arch/sh/kernel/dumpstack.c @@ -16,30 +16,31 @@ #include #include -void dump_mem(const char *str, unsigned long bottom, unsigned long top) +void dump_mem(const char *str, const char *loglvl, + unsigned long bottom, unsigned long top) { unsigned long p; int i; - printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top); + printk("%s%s(0x%08lx to 0x%08lx)\n", loglvl, str, bottom, top); for (p = bottom & ~31; p < top; ) { - printk("%04lx: ", p & 0xffff); + printk("%s%04lx: ", loglvl, p & 0xffff); for (i = 0; i < 8; i++, p += 4) { unsigned int val; if (p < bottom || p >= top) - printk(" "); + printk("%s ", loglvl); else { if (__get_user(val, (unsigned int __user *)p)) { - printk("\n"); + printk("%s\n", loglvl); return; } - printk("%08x ", val); + printk("%s%08x ", loglvl, val); } } - printk("\n"); + printk("%s\n", loglvl); } } @@ -156,7 +157,7 @@ void show_stack(struct task_struct *tsk, sp = (unsigned long *)tsk->thread.sp; stack = (unsigned long)sp; - dump_mem("Stack: ", stack, THREAD_SIZE + + dump_mem("Stack: ", KERN_DEFAULT, stack, THREAD_SIZE + (unsigned long)task_stack_page(tsk)); show_trace(tsk, sp, NULL); } --- a/arch/sh/kernel/traps.c~sh-add-loglvl-to-dump_mem +++ a/arch/sh/kernel/traps.c @@ -38,8 +38,8 @@ void die(const char *str, struct pt_regs task_pid_nr(current), task_stack_page(current) + 1); if (!user_mode(regs) || in_interrupt()) - dump_mem("Stack: ", regs->regs[15], THREAD_SIZE + - (unsigned long)task_stack_page(current)); + dump_mem("Stack: ", KERN_DEFAULT, regs->regs[15], + THREAD_SIZE + (unsigned long)task_stack_page(current)); notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV); _