/* * digi00x-transaction.c - a part of driver for Digidesign Digi 002/003 family * * Copyright (c) 2014-2015 Takashi Sakamoto * * Licensed under the terms of the GNU General Public License, version 2. */ #include #include "digi00x.h" static int fill_midi_message(struct snd_rawmidi_substream *substream, u8 *buf) { int bytes; buf[0] = 0x80; bytes = snd_rawmidi_transmit_peek(substream, buf + 1, 2); if (bytes >= 0) buf[3] = 0xc0 | bytes; return bytes; } static void handle_midi_control(struct snd_dg00x *dg00x, __be32 *buf, unsigned int length) { struct snd_rawmidi_substream *substream; unsigned int i; unsigned int len; u8 *b; substream = ACCESS_ONCE(dg00x->in_control); if (substream == NULL) return; length /= 4; for (i = 0; i < length; i++) { b = (u8 *)&buf[i]; len = b[3] & 0xf; if (len > 0) snd_rawmidi_receive(dg00x->in_control, b + 1, len); } } static void handle_unknown_message(struct snd_dg00x *dg00x, unsigned long long offset, __be32 *buf) { unsigned long flags; spin_lock_irqsave(&dg00x->lock, flags); dg00x->msg = be32_to_cpu(*buf); spin_unlock_irqrestore(&dg00x->lock, flags); wake_up(&dg00x->hwdep_wait); } static void handle_message(struct fw_card *card, struct fw_request *request, int tcode, int destination, int source, int generation, unsigned long long offset, void *data, size_t length, void *callback_data) { struct snd_dg00x *dg00x = callback_data; __be32 *buf = (__be32 *)data; if (offset == dg00x->async_handler.offset) handle_unknown_message(dg00x, offset, buf); else if (offset == dg00x->async_handler.offset + 4) handle_midi_control(dg00x, buf, length); fw_send_response(card, request, RCODE_COMPLETE); } int snd_dg00x_transaction_reregister(struct snd_dg00x *dg00x) { struct fw_device *device = fw_parent_device(dg00x->unit); __be32 data[2]; int err; /* Unknown. 4bytes. */ data[0] = cpu_to_be32((device->card->node_id << 16) | (dg00x->async_handler.offset >> 32)); data[1] = cpu_to_be32(dg00x->async_handler.offset); err = snd_fw_transaction(dg00x->unit, TCODE_WRITE_BLOCK_REQUEST, DG00X_ADDR_BASE + DG00X_OFFSET_MESSAGE_ADDR, &data, sizeof(data), 0); if (err < 0) return err; /* Asynchronous transactions for MIDI control message. */ data[0] = cpu_to_be32((device->card->node_id << 16) | (dg00x->async_handler.offset >> 32)); data[1] = cpu_to_be32(dg00x->async_handler.offset + 4); return snd_fw_transaction(dg00x->unit, TCODE_WRITE_BLOCK_REQUEST, DG00X_ADDR_BASE + DG00X_OFFSET_MIDI_CTL_ADDR, &data, sizeof(data), 0); } int snd_dg00x_transaction_register(struct snd_dg00x *dg00x) { static const struct fw_address_region resp_register_region = { .start = 0xffffe0000000ull, .end = 0xffffe000ffffull, }; int err; dg00x->async_handler.length = 12; dg00x->async_handler.address_callback = handle_message; dg00x->async_handler.callback_data = dg00x; err = fw_core_add_address_handler(&dg00x->async_handler, &resp_register_region); if (err < 0) return err; err = snd_dg00x_transaction_reregister(dg00x); if (err < 0) goto error; err = snd_fw_async_midi_port_init(&dg00x->out_control, dg00x->unit, DG00X_ADDR_BASE + DG00X_OFFSET_MMC, 4, fill_midi_message); if (err < 0) goto error; return err; error: fw_core_remove_address_handler(&dg00x->async_handler); dg00x->async_handler.callback_data = NULL; return err; } void snd_dg00x_transaction_unregister(struct snd_dg00x *dg00x) { if (dg00x->async_handler.callback_data == NULL) return; snd_fw_async_midi_port_destroy(&dg00x->out_control); fw_core_remove_address_handler(&dg00x->async_handler); dg00x->async_handler.callback_data = NULL; } ve'/>
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authorOndrej Kozina <okozina@redhat.com>2017-01-31 15:47:11 +0100
committerMike Snitzer <snitzer@redhat.com>2017-02-03 10:26:14 -0500
commitf5b0cba8f23915e92932f11eb063e37d70556a89 (patch)
tree19f7ccac636459333cca52027914d19084b1392b /drivers/usb/misc/ftdi-elan.c
parent4087a1fffe38106e10646606a27f10d40451862d (diff)
dm crypt: replace RCU read-side section with rwsem
The lockdep splat below hints at a bug in RCU usage in dm-crypt that was introduced with commit c538f6ec9f56 ("dm crypt: add ability to use keys from the kernel key retention service"). The kernel keyring function user_key_payload() is in fact a wrapper for rcu_dereference_protected() which must not be called with only rcu_read_lock() section mark. Unfortunately the kernel keyring subsystem doesn't currently provide an interface that allows the use of an RCU read-side section. So for now we must drop RCU in favour of rwsem until a proper function is made available in the kernel keyring subsystem. =============================== [ INFO: suspicious RCU usage. ] 4.10.0-rc5 #2 Not tainted ------------------------------- ./include/keys/user-type.h:53 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by cryptsetup/6464: #0: (&md->type_lock){+.+.+.}, at: [<ffffffffa02472a2>] dm_lock_md_type+0x12/0x20 [dm_mod] #1: (rcu_read_lock){......}, at: [<ffffffffa02822f8>] crypt_set_key+0x1d8/0x4b0 [dm_crypt] stack backtrace: CPU: 1 PID: 6464 Comm: cryptsetup Not tainted 4.10.0-rc5 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-1.fc24 04/01/2014 Call Trace: dump_stack+0x67/0x92 lockdep_rcu_suspicious+0xc5/0x100 crypt_set_key+0x351/0x4b0 [dm_crypt] ? crypt_set_key+0x1d8/0x4b0 [dm_crypt] crypt_ctr+0x341/0xa53 [dm_crypt] dm_table_add_target+0x147/0x330 [dm_mod] table_load+0x111/0x350 [dm_mod] ? retrieve_status+0x1c0/0x1c0 [dm_mod] ctl_ioctl+0x1f5/0x510 [dm_mod] dm_ctl_ioctl+0xe/0x20 [dm_mod] do_vfs_ioctl+0x8e/0x690 ? ____fput+0x9/0x10 ? task_work_run+0x7e/0xa0 ? trace_hardirqs_on_caller+0x122/0x1b0 SyS_ioctl+0x3c/0x70 entry_SYSCALL_64_fastpath+0x18/0xad RIP: 0033:0x7f392c9a4ec7 RSP: 002b:00007ffef6383378 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffef63830a0 RCX: 00007f392c9a4ec7 RDX: 000000000124fcc0 RSI: 00000000c138fd09 RDI: 0000000000000005 RBP: 00007ffef6383090 R08: 00000000ffffffff R09: 00000000012482b0 R10: 2a28205d34383336 R11: 0000000000000246 R12: 00007f392d803a08 R13: 00007ffef63831e0 R14: 0000000000000000 R15: 00007f392d803a0b Fixes: c538f6ec9f56 ("dm crypt: add ability to use keys from the kernel key retention service") Reported-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Ondrej Kozina <okozina@redhat.com> Reviewed-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/usb/misc/ftdi-elan.c')