user/sven/linux.git/lib/dynamic_debug.c, branch v5.7.17

dyndbg: fix a BUG_ON in ddebug_describe_flags

2020-08-19T06:23:41Z

[ Upstream commit f678ce8cc3cb2ad29df75d8824c74f36398ba871 ] ddebug_describe_flags() currently fills a caller provided string buffer, after testing its size (also passed) in a BUG_ON. Fix this by replacing them with a known-big-enough string buffer wrapped in a struct, and passing that instead. Also simplify ddebug_describe_flags() flags parameter from a struct to a member in that struct, and hoist the member deref up to the caller. This makes the function reusable (soon) where flags are unpacked. Acked-by: Signed-off-by: Jim Cromie Link: https://lore.kernel.org/r/20200719231058.1586423-8-jim.cromie@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

lib/dynamic_debug.c: use address-of operator on section symbols

2020-04-07T17:43:43Z

Clang warns: ../lib/dynamic_debug.c:1034:24: warning: array comparison always evaluates to false [-Wtautological-compare] if (__start___verbose == __stop___verbose) { ^ 1 warning generated. These are not true arrays, they are linker defined symbols, which are just addresses. Using the address of operator silences the warning and does not change the resulting assembly with either clang/ld.lld or gcc/ld (tested with diff + objdump -Dr). Suggested-by: Nick Desaulniers Signed-off-by: Nathan Chancellor Signed-off-by: Andrew Morton Acked-by: Jason Baron Link: https://github.com/ClangBuiltLinux/linux/issues/894 Link: http://lkml.kernel.org/r/20200220051320.10739-1-natechancellor@gmail.com Signed-off-by: Linus Torvalds

dynamic_debug: allow to work if debugfs is disabled

2020-02-12T22:15:53Z

With the realization that having debugfs enabled on "production" systems is generally not a good idea, debugfs is being disabled from more and more platforms over time. However, the functionality of dynamic debugging still is needed at times, and since it relies on debugfs for its user api, having debugfs disabled also forces dynamic debug to be disabled. To get around this, also create the "control" file for dynamic_debug in procfs. This allows people turn on debugging as needed at runtime for individual driverfs and subsystems. Reported-by: many different companies Cc: Jason Baron Acked-by: Will Deacon Link: https://lore.kernel.org/r/20200210211142.GB1373304@kroah.com Signed-off-by: Greg Kroah-Hartman

lib: dynamic_debug: no need to check return value of debugfs_create functions

2019-06-18T11:47:24Z

When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Cc: linux-kernel@vger.kernel.org Acked-by: Jason Baron Signed-off-by: Greg Kroah-Hartman

RDMA/core: Introduce RDMA subsystem ibdev_* print functions

2019-05-01T16:29:28Z

Similarly to dev/netdev/etc printk helpers, add standard printk helpers for the RDMA subsystem. Example output: efa 0000:00:06.0 efa_0: Hello World! efa_0: Hello World! (no parent device set) (NULL ib_device): Hello World! (ibdev is NULL) Cc: Jason Baron Suggested-by: Jason Gunthorpe Suggested-by: Leon Romanovsky Signed-off-by: Gal Pressman Reviewed-by: Leon Romanovsky Reviewed-by: Shiraz Saleem Reviewed-by: Dennis Dalessandro Signed-off-by: Doug Ledford

dynamic_debug: move pr_err from module.c to ddebug_add_module

2019-03-08T02:32:00Z

This serves two purposes: First, we get a diagnostic if (though extremely unlikely), any of the calls of ddebug_add_module for built-in code fails, effectively disabling dynamic_debug. Second, I want to make struct _ddebug opaque, and avoid accessing any of its members outside dynamic_debug.[ch]. Link: http://lkml.kernel.org/r/20190212214150.4807-9-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes Acked-by: Jason Baron Cc: David Sterba Cc: Greg Kroah-Hartman Cc: Ingo Molnar Cc: Petr Mladek Cc: "Rafael J . Wysocki" Cc: Steven Rostedt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

dynamic_debug: remove unused EXPORT_SYMBOLs

2019-03-08T02:32:00Z

The only caller of ddebug_{add,remove}_module outside dynamic_debug.c is kernel/module.c, which is obviously not itself modular (though it would be an interesting exercise to make that happen...). I also fail to see how these interfaces can be used by modules, in-tree or not. Link: http://lkml.kernel.org/r/20190212214150.4807-8-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes Acked-by: Jason Baron Cc: David Sterba Cc: Greg Kroah-Hartman Cc: Ingo Molnar Cc: Petr Mladek Cc: "Rafael J . Wysocki" Cc: Steven Rostedt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

dynamic_debug: use pointer comparison in ddebug_remove_module

2019-03-08T02:32:00Z

Now that we store the passed-in string directly in ddebug_add_module, we can use pointer equality instead of strcmp. This is a little more efficient, but more importantly, this also makes the code somewhat more correct: Currently, if one loads and then unloads a module whose name happens to match the KBUILD_MODNAME of some built-in functionality (which need not even be modular at all), all of their dynamic debug entries vanish along with those of the actual module. For example, loading and unloading a core.ko hides all pr_debugs from drivers/base/core.c and other built-in files called core.c (incidentally, there is an in-tree module whose name is core, but I just tested this with an out-of-tree trivial one). Link: http://lkml.kernel.org/r/20190212214150.4807-7-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes Acked-by: Jason Baron Cc: David Sterba Cc: Greg Kroah-Hartman Cc: Ingo Molnar Cc: Petr Mladek Cc: "Rafael J . Wysocki" Cc: Steven Rostedt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

dynamic_debug: don't duplicate modname in ddebug_add_module

2019-03-08T02:32:00Z

For built-in modules, we're already reusing the passed-in string via kstrdup_const(). But for actual modules (i.e. when we're called from dynamic_debug_setup in module.c), the passed-in string (which points at the name[] array inside struct module) is also guaranteed to live at least as long as the struct ddebug_table, since free_module() calls ddebug_remove_module(). Link: http://lkml.kernel.org/r/20190212214150.4807-6-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes Acked-by: Jason Baron Cc: David Sterba Cc: Greg Kroah-Hartman Cc: Ingo Molnar Cc: Petr Mladek Cc: "Rafael J . Wysocki" Cc: Steven Rostedt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

jump_label: move 'asm goto' support test to Kconfig

2019-01-06T00:46:51Z

Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label". The jump label is controlled by HAVE_JUMP_LABEL, which is defined like this: #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) # define HAVE_JUMP_LABEL #endif We can improve this by testing 'asm goto' support in Kconfig, then make JUMP_LABEL depend on CC_HAS_ASM_GOTO. Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will match to the real kernel capability. Signed-off-by: Masahiro Yamada Acked-by: Michael Ellerman (powerpc) Tested-by: Sedat Dilek