kernel.git/arch/powerpc/xmon/nonstdio.c, branch master

powerpc/xmon: Change printk() to pr_cont()

2020-12-04T10:56:30Z

Since some time now, printk() adds carriage return, leading to unusable xmon output if there is no udbg backend available: [ 54.288722] sysrq: Entering xmon [ 54.292209] Vector: 0 at [cace3d2c] [ 54.292274] pc: [ 54.292331] c0023650 [ 54.292468] : xmon+0x28/0x58 [ 54.292519] [ 54.292574] lr: [ 54.292630] c0023724 [ 54.292749] : sysrq_handle_xmon+0xa4/0xfc [ 54.292801] [ 54.292867] sp: cace3de8 [ 54.292931] msr: 9032 [ 54.292999] current = 0xc28d0000 [ 54.293072] pid = 377, comm = sh [ 54.293157] Linux version 5.10.0-rc6-s3k-dev-01364-gedf13f0ccd76-dirty (root@po17688vm.idsi0.si.c-s.fr) (powerpc64-linux-gcc (GCC) 10.1.0, GNU ld (GNU Binutils) 2.34) #4211 PREEMPT Fri Dec 4 09:32:11 UTC 2020 [ 54.293287] enter ? for help [ 54.293470] [cace3de8] [ 54.293532] c0023724 [ 54.293654] sysrq_handle_xmon+0xa4/0xfc [ 54.293711] (unreliable) ... [ 54.296002] [ 54.296159] --- Exception: c01 (System Call) at [ 54.296217] 0fd4e784 [ 54.296303] [ 54.296375] SP (7fca6ff0) is in userspace [ 54.296431] mon> [ 54.296484] Use pr_cont() instead. Fixes: 4bcc595ccd80 ("printk: reinstate KERN_CONT for printing continuation lines") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Christophe Leroy [mpe: Mention that it only happens when udbg is not available] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/c8a6ec704416ecd5ff2bd26213c9bc026bdd19de.1607077340.git.christophe.leroy@csgroup.eu

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc/xmon: Paged output for paca display

2015-10-15T09:32:01Z

The paca display is already more than 24 lines, which can be problematic if you have an old school 80x24 terminal, or more likely you are on a virtual terminal which does not scroll for whatever reason. This patch adds a new command "#", which takes a single (hex) numeric argument: lines per page. It will cause the output of "dp" and "dpa" to be broken into pages, if necessary. Sample output: 0:mon> # 10 0:mon> dp1 paca for cpu 0x1 @ c00000000fdc0480: possible = yes present = yes online = yes lock_token = 0x8000 (0x8) paca_index = 0x1 (0xa) kernel_toc = 0xc000000000eb2400 (0x10) kernelbase = 0xc000000000000000 (0x18) kernel_msr = 0xb000000000001032 (0x20) emergency_sp = 0xc00000003ffe8000 (0x28) mc_emergency_sp = 0xc00000003ffe4000 (0x2e0) in_mce = 0x0 (0x2e8) data_offset = 0x7f170000 (0x30) hw_cpu_id = 0x8 (0x38) cpu_start = 0x1 (0x3a) kexec_state = 0x0 (0x3b) [Hit a key (a:all, q:truncate, any:next page)] 0:mon> __current = 0xc00000007e696620 (0x290) kstack = 0xc00000007e6ebe30 (0x298) stab_rr = 0xb (0x2a0) saved_r1 = 0xc00000007ef37860 (0x2a8) trap_save = 0x0 (0x2b8) soft_enabled = 0x0 (0x2ba) irq_happened = 0x1 (0x2bb) io_sync = 0x0 (0x2bc) irq_work_pending = 0x0 (0x2bd) nap_state_lost = 0x0 (0x2be) 0:mon> Signed-off-by: Sam Bobroff [mpe: Use bool, make some variables static] Signed-off-by: Michael Ellerman

powerpc/xmon: avoid format string leaking to printk

2014-06-11T07:04:03Z

This makes sure format strings cannot leak into printk (the string has already been correctly processed for format arguments). Signed-off-by: Kees Cook Signed-off-by: Benjamin Herrenschmidt

powerpc/xmon: Fallback to printk() in xmon_printf() if udbg is not setup

2012-11-15T02:00:02Z

It is possible to configure a kernel which has xmon enabled, but has no udbg backend to provide IO. This can make xmon rather confusing, as it produces no output, blocks for two seconds, and then returns. As a last resort we can instead try to printk(), which may deadlock or otherwise crash, but tries quite hard not to. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt

powerpc/xmon: Merge start.c into nonstdio.c

2012-11-15T01:59:46Z

The routines in start.c are only ever called from nonstdio.c, so if we move them in there they can become static which is nice. I suspect the idea behind the separation was that start.c could be replaced in order to build xmon in userland. If anyone still cares about doing that we could handle that with an ifdef or two. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt

powerpc/xmon: Make xmon_getchar() static

2012-11-15T01:59:43Z

xmon_getchar() is only called from within nonstdio.c, so make it static. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt

powerpc/xmon: Remove unused xmon_expect() & xmon_read_poll()

2012-11-15T01:59:37Z

It looks like xmon_expect() was used for doing xmon over a modem (!?), that code was dropped in 2005 in commit 51d3082 "Unify udbg (#2)". Once xmon_expect() is gone xmon_read_poll() is unused, drop it too. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt

[POWERPC] fix showing xmon help

2007-07-22T11:30:58Z

In some configuration, xmon help string is larger than xmon_printf buffer. We need not to use printf. This patch adds xmon_puts and change to use it to show help string. Signed-off-by: Kou Ishizaki Signed-off-by: Paul Mackerras

powerpc: Simplify and clean up the xmon terminal I/O

2005-11-08T11:55:08Z

This factors out the common bits of arch/powerpc/xmon/start_*.c into a new nonstdio.c, and removes some stuff that was supposed to make xmon's I/O routines somewhat stdio-like but was never used. It also makes the parsing of the xmon= command line option common, so that ppc32 can now use xmon={off,on,early} also. Signed-off-by: Paul Mackerras