Commit Graph

10 Commits

Author SHA1 Message Date
Christophe Leroy 7c6c86b36a powerpc/xmon: Change printk() to pr_cont()
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]  <no input ...>

Use pr_cont() instead.

Fixes: 4bcc595ccd ("printk: reinstate KERN_CONT for printing continuation lines")
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Mention that it only happens when udbg is not available]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c8a6ec704416ecd5ff2bd26213c9bc026bdd19de.1607077340.git.christophe.leroy@csgroup.eu
2020-12-04 21:56:30 +11:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
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 <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Sam bobroff 958b7c8050 powerpc/xmon: Paged output for paca display
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 <sam.bobroff@au1.ibm.com>
[mpe: Use bool, make some variables static]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-15 20:32:01 +11:00
Kees Cook 50b66dbf87 powerpc/xmon: avoid format string leaking to printk
This makes sure format strings cannot leak into printk (the string has
already been correctly processed for format arguments).

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 17:04:03 +10:00
Michael Ellerman b2bb65f680 powerpc/xmon: Fallback to printk() in xmon_printf() if udbg is not setup
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 <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-11-15 13:00:02 +11:00
Michael Ellerman 33b5cd6866 powerpc/xmon: Merge start.c into nonstdio.c
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 <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-11-15 12:59:46 +11:00
Michael Ellerman 88c6d62641 powerpc/xmon: Make xmon_getchar() static
xmon_getchar() is only called from within nonstdio.c, so make it static.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-11-15 12:59:43 +11:00
Michael Ellerman eb1c2abb61 powerpc/xmon: Remove unused xmon_expect() & xmon_read_poll()
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 <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-11-15 12:59:37 +11:00
Ishizaki Kou 4d404edce3 [POWERPC] fix showing xmon help
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 <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-22 21:30:58 +10:00
Paul Mackerras fca5dcd483 powerpc: Simplify and clean up the xmon terminal I/O
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 <paulus@samba.org>
2005-11-08 22:55:08 +11:00