user/sven/linux.git/drivers/base/devcoredump.c, branch v6.7.6

devcoredump: Send uevent once devcd is ready

2023-11-28T19:39:18Z

dev_coredumpm() creates a devcoredump device and adds it to the core kernel framework which eventually end up sending uevent to the user space and later creates a symbolic link to the failed device. An application running in userspace may be interested in this symbolic link to get the name of the failed device. In a issue scenario, once uevent sent to the user space it start reading '/sys/class/devcoredump/devcdX/failing_device' to get the actual name of the device which might not been created and it is in its path of creation. To fix this, suppress sending uevent till the failing device symbolic link gets created and send uevent once symbolic link is created successfully. Fixes: 833c95456a70 ("device coredump: add new device coredump class") Signed-off-by: Mukesh Ojha Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/1700232572-25823-1-git-send-email-quic_mojha@quicinc.com Signed-off-by: Greg Kroah-Hartman

driver core: class: mark the struct class for sysfs callbacks as constant

2023-03-29T05:54:58Z

struct class should never be modified in a sysfs callback as there is nothing in the structure to modify, and frankly, the structure is almost never used in a sysfs callback, so mark it as constant to allow struct class to be moved to read-only memory. While we are touching all class sysfs callbacks also mark the attribute as constant as it can not be modified. The bonding code still uses this structure so it can not be removed from the function callbacks. Cc: "David S. Miller" Cc: "Rafael J. Wysocki" Cc: Bartosz Golaszewski Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Jens Axboe Cc: Johannes Berg Cc: Linus Walleij Cc: Minchan Kim Cc: Miquel Raynal Cc: Namjae Jeon Cc: Paolo Abeni Cc: Russ Weight Cc: Sergey Senozhatsky Cc: Steve French Cc: Vignesh Raghavendra Cc: linux-cifs@vger.kernel.org Cc: linux-gpio@vger.kernel.org Cc: linux-mtd@lists.infradead.org Cc: linux-rdma@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: netdev@vger.kernel.org Reviewed-by: Luis Chamberlain Link: https://lore.kernel.org/r/20230325084537.3622280-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

drivers: remove struct module * setting from struct class

2023-03-17T14:16:27Z

There is no need to manually set the owner of a struct class, as the registering function does it automatically, so remove all of the explicit settings from various drivers that did so as it is unneeded. This allows us to remove this pointer entirely from this structure going forward. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230313181843.1207845-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

devcoredump : Serialize devcd_del work

2022-09-24T12:01:40Z

In following scenario(diagram), when one thread X running dev_coredumpm() adds devcd device to the framework which sends uevent notification to userspace and another thread Y reads this uevent and call to devcd_data_write() which eventually try to delete the queued timer that is not initialized/queued yet. So, debug object reports some warning and in the meantime, timer is initialized and queued from X path. and from Y path, it gets reinitialized again and timer->entry.pprev=NULL and try_to_grab_pending() stucks. To fix this, introduce mutex and a boolean flag to serialize the behaviour. cpu0(X) cpu1(Y) dev_coredump() uevent sent to user space device_add() ======================> user space process Y reads the uevents writes to devcd fd which results into writes to devcd_data_write() mod_delayed_work() try_to_grab_pending() del_timer() debug_assert_init() INIT_DELAYED_WORK() schedule_delayed_work() debug_object_fixup() timer_fixup_assert_init() timer_setup() do_init_timer() /* Above call reinitializes the timer to timer->entry.pprev=NULL and this will be checked later in timer_pending() call. */ timer_pending() !hlist_unhashed_lockless(&timer->entry) !h->pprev /* del_timer() checks h->pprev and finds it to be NULL due to which try_to_grab_pending() stucks. */ Link: https://lore.kernel.org/lkml/2e1f81e2-428c-f11f-ce92-eb11048cb271@quicinc.com/ Signed-off-by: Mukesh Ojha Link: https://lore.kernel.org/r/1663073424-13663-1-git-send-email-quic_mojha@quicinc.com Signed-off-by: Greg Kroah-Hartman

devcoredump: remove contact information

2021-06-04T13:05:44Z

That email address hasn't existed for a long time, and the mailing address is pretty useless; remove all of this. Signed-off-by: Johannes Berg Link: https://lore.kernel.org/r/20210528100314.d419f6e8e2d2.Ica8076036c755d6f782becd62d04c41361323130@changeid Signed-off-by: Greg Kroah-Hartman

devcoredump: fix kernel-doc warning

2021-04-02T14:40:08Z

remove make W=1 warnings drivers/base/devcoredump.c:208: warning: Function parameter or member 'data' not described in 'devcd_free_sgtable' drivers/base/devcoredump.c:208: warning: Excess function parameter 'table' description in 'devcd_free_sgtable' drivers/base/devcoredump.c:225: warning: expecting prototype for devcd_read_from_table(). Prototype was for devcd_read_from_sgtable() instead Signed-off-by: Pierre-Louis Bossart Link: https://lore.kernel.org/r/20210331232614.304591-8-pierre-louis.bossart@linux.intel.com Signed-off-by: Greg Kroah-Hartman

devcoredump: avoid -Wempty-body warnings

2021-03-23T14:04:59Z

Cleaning out the last -Wempty-body warnings found some interesting cases with empty macros, along with harmless warnings like this one: drivers/base/devcoredump.c: In function 'dev_coredumpm': drivers/base/devcoredump.c:297:56: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body] 297 | /* nothing - symlink will be missing */; | ^ drivers/base/devcoredump.c:301:56: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body] 301 | /* nothing - symlink will be missing */; | ^ Randy tried addressing this one before, and there were multiple other ideas in that thread. Add a runtime warning and code comment here. Link: https://lore.kernel.org/lkml/20200418184111.13401-8-rdunlap@infradead.org/ Cc: Randy Dunlap Cc: Matthew Wilcox Signed-off-by: Arnd Bergmann Link: https://lore.kernel.org/r/20210322114258.3420937-1-arnd@kernel.org Signed-off-by: Greg Kroah-Hartman

drivers core: Miscellaneous changes for sysfs_emit

2020-10-02T11:12:07Z

Change additional instances that could use sysfs_emit and sysfs_emit_at that the coccinelle script could not convert. o macros creating show functions with ## concatenation o unbound sprintf uses with buf+len for start of output to sysfs_emit_at o returns with ?: tests and sprintf to sysfs_emit o sysfs output with struct class * not struct device * arguments Miscellanea: o remove unnecessary initializations around these changes o consistently use int len for return length of show functions o use octal permissions and not S_ o rename a few show function names so DEVICE_ATTR_ can be used o use DEVICE_ATTR_ADMIN_RO where appropriate o consistently use const char *output for strings o checkpatch/style neatening Signed-off-by: Joe Perches Link: https://lore.kernel.org/r/8bc24444fe2049a9b2de6127389b57edfdfe324d.1600285923.git.joe@perches.com Signed-off-by: Greg Kroah-Hartman

devcoredump: fix typo in comment

2019-08-15T15:38:11Z

s/dev_coredumpmsg/dev_coredumpsg/ in the kernel-doc Reviewed-by: Chaitanya Kulkarni Signed-off-by: Akinobu Mita Link: https://lore.kernel.org/r/1564243146-5681-3-git-send-email-akinobu.mita@gmail.com Signed-off-by: Johannes Berg Link: https://lore.kernel.org/r/20190731100007.32684-2-johannes@sipsolutions.net Signed-off-by: Greg Kroah-Hartman

devcoredump: use memory_read_from_buffer

2019-08-15T15:38:11Z

Use memory_read_from_buffer() to simplify devcd_readv(). Reviewed-by: Chaitanya Kulkarni Reviewed-by: Johannes Berg Signed-off-by: Akinobu Mita Link: https://lore.kernel.org/r/1564243146-5681-2-git-send-email-akinobu.mita@gmail.com Signed-off-by: Johannes Berg Link: https://lore.kernel.org/r/20190731100007.32684-1-johannes@sipsolutions.net Signed-off-by: Greg Kroah-Hartman