user/sven/linux.git/kernel/debug/kdb/kdb_io.c, branch v4.1.2

kdb: Const qualifier for kdb_getstr's prompt argument

2015-02-19T18:39:03Z

All current callers of kdb_getstr() can pass constant pointers via the prompt argument. This patch adds a const qualification to make explicit the fact that this is safe. Signed-off-by: Daniel Thompson Signed-off-by: Jason Wessel

kdb: Provide forward search at more prompt

2015-02-19T18:39:03Z

Currently kdb allows the output of comamnds to be filtered using the | grep feature. This is useful but does not permit the output emitted shortly after a string match to be examined without wading through the entire unfiltered output of the command. Such a feature is particularly useful to navigate function traces because these traces often have a useful trigger string *before* the point of interest. This patch reuses the existing filtering logic to introduce a simple forward search to kdb that can be triggered from the more prompt. Signed-off-by: Daniel Thompson Signed-off-by: Jason Wessel

kdb: Avoid printing KERN_ levels to consoles

2015-02-19T18:39:02Z

Currently when kdb traps printk messages then the raw log level prefix (consisting of '\001' followed by a numeral) does not get stripped off before the message is issued to the various I/O handlers supported by kdb. This causes annoying visual noise as well as causing problems grepping for ^. It is also a change of behaviour compared to normal usage of printk() usage. For example -h ends up with different output to that of kdb's "sr h". This patch addresses the problem by stripping log levels from messages before they are issued to the I/O handlers. printk() which can also act as an i/o handler in some cases is special cased; if the caller provided a log level then the prefix will be preserved when sent to printk(). The addition of non-printable characters to the output of kdb commands is a regression, albeit and extremely elderly one, introduced by commit 04d2c8c83d0e ("printk: convert the format for KERN_ to a 2 byte pattern"). Note also that this patch does *not* restore the original behaviour from v3.5. Instead it makes printk() from within a kdb command display the message without any prefix (i.e. like printk() normally does). Signed-off-by: Daniel Thompson Cc: Joe Perches Cc: stable@vger.kernel.org Signed-off-by: Jason Wessel

kernel/printk: use symbolic defines for console loglevels

2014-06-04T23:54:17Z

... instead of naked numbers. Stuff in sysrq.c used to set it to 8 which is supposed to mean above default level so set it to DEBUG instead as we're terminating/killing all tasks and we want to be verbose there. Also, correct the check in x86_64_start_kernel which should be >= as we're clearly issuing the string there for all debug levels, not only the magical 10. Signed-off-by: Borislav Petkov Acked-by: Kees Cook Acked-by: Randy Dunlap Cc: Joe Perches Cc: Valdis Kletnieks Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kdb,vt_console: Fix missed data due to pager overruns

2012-10-12T11:37:35Z

It is possible to miss data when using the kdb pager. The kdb pager does not pay attention to the maximum column constraint of the screen or serial terminal. This result is not incrementing the shown lines correctly and the pager will print more lines that fit on the screen. Obviously that is less than useful when using a VGA console where you cannot scroll back. The pager will now look at the kdb_buffer string to see how many characters are printed. It might not be perfect considering you can output ASCII that might move the cursor position, but it is a substantially better approximation for viewing dmesg and trace logs. This also means that the vt screen needs to set the kdb COLUMNS variable. Cc: Signed-off-by: Jason Wessel

kdb: Remove cpu from the more prompt

2012-07-31T13:16:43Z

Having the CPU in the more prompt is completely redundent vs the standard kdb prompt, and it also wastes 32 bytes on the stack. Signed-off-by: Jason Wessel

kdb: Fix smatch warning on dbg_io_ops->is_console

2012-03-29T22:41:23Z

The Smatch tool warned that the change from commit b8adde8dd (kdb: Avoid using dbg_io_ops until it is initialized) should add another null check later in the kdb_printf(). It is worth noting that the second use of dbg_io_ops->is_console is protected by the KDB_PAGER state variable which would only get set when kdb is fully active and initialized. If we ever encounter changes or defects in the KDB_PAGER state we do not want to crash the kernel in a kdb_printf/printk. CC: Tim Bird Reported-by: Dan Carpenter Signed-off-by: Jason Wessel

kdb: Avoid using dbg_io_ops until it is initialized

2012-03-22T20:07:16Z

This fixes a bug with setting a breakpoint during kdb initialization (from kdb_cmds). Any call to kdb_printf() before the initialization of the kgdboc serial console driver (which happens much later during bootup than kdb_init), results in kernel panic due to the use of dbg_io_ops before it is initialized. Signed-off-by: Tim Bird Signed-off-by: Jason Wessel

kdb,kgdb: Allow arbitrary kgdb magic knock sequences

2011-08-01T18:23:59Z

The first packet that gdb sends when the kernel is in kdb mode seems to change with every release of gdb. Instead of continuing to add many different gdb packets, change kdb to automatically look for any thing that looks like a gdb packet. Example 1 cold start test: echo g > /proc/sysrq-trigger $D#44+ Example 2 cold start test: echo g > /proc/sysrq-trigger $3#33 The second one should re-enter kdb's shell right away and is purely a test. Signed-off-by: Jason Wessel

kdb: Remove all references to DOING_KGDB2

2011-08-01T18:23:59Z

The DOING_KGDB2 was originally a state variable for one of the two ways to automatically transition from kdb to kgdb. Purge all these variables and just use one single state for the transition. Signed-off-by: Jason Wessel