> We had few customers who met panics in n_tty_read() with following > backtrace: > > #8 [ffff880018b8dcd0] page_fault at ffffffff814ddfe5 > [exception RIP: n_tty_read+0x2c9] > <register output removed> > #9 [ffff880018b8dea0] tty_read at ffffffff81300b16 > #10 [ffff880018b8def0] vfs_read at ffffffff81172f85 > #11 [ffff880018b8df30] sys_read at ffffffff811730c1 > #12 [ffff880018b8df80] system_call_fastpath at ffffffff8100b172 What serial driver are they using when they hit this ? > > My patch for this panic is attached (tty_panic.patch), in short - I > believe that we need to hold &tty->read_lock while checking > tty->read_cnt in while-loop condition in n_tty_read() here: We can't hold the lock for the loop because we touch user space memory. Alan -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
