mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-02-16 20:05:13 -05:00
32ecc75ded
Sometimes during probing and registration of pn533_i2c NULL pointer dereference happens. Reproduced in cycle of inserting and removing pn533_i2c and pn533 modules. Backtrace: [<8004205c>] (__queue_work) from [<80042324>] (queue_work_on+0x50/0x5c) r10:acdc7c80 r9:8006b330 r8:ac0dfb40 r7:ac50c600 r6:00000004 r5:acbbee40 r4:600f0113 [<800422d4>] (queue_work_on) from [<7f7d5b6c>] (pn533_recv_frame+0x158/0x1fc [pn533]) r7:ffffff87 r6:00000000 r5:acbbee40 r4:acbbee00 [<7f7d5a14>] (pn533_recv_frame [pn533]) from [<7f7df4b8>] (pn533_i2c_irq_thread_fn+0x184/0x) r6:acb2a000 r5:00000000 r4:acdc7b90 [<7f7df334>] (pn533_i2c_irq_thread_fn [pn533_i2c]) from [<8006b354>] (irq_thread_fn+0x24/0x) r7:00000000 r6:accde000 r5:ac0dfb40 r4:acdc7c80 ... Seems there is some race condition due registration of irq handler until all data stuctures that could be needed are ready. So I re-ordered some ops. After this, problem has gone. Changes in USB part was not tested, but it should not break anything. Signed-off-by: Andrey Rusalin <arusalin@dev.rtsoft.ru> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.