diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-06-05 21:51:48 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-06-06 02:28:41 +0300 |
| commit | e1cff7002b716bd0b5f5f4afd4273c99aa8644be (patch) | |
| tree | a815db0dcbfd44b0cec1ba3d77a989864afdea74 /net/bluetooth/hci_sync.c | |
| parent | d717180e7f9775d468f415c10a4a474640146001 (diff) | |
| download | linux-e1cff7002b716bd0b5f5f4afd4273c99aa8644be.tar.xz | |
bluetooth: don't use bitmaps for random flag accesses
The bluetooth code uses our bitmap infrastructure for the two bits (!)
of connection setup flags, and in the process causes odd problems when
it converts between a bitmap and just the regular values of said bits.
It's completely pointless to do things like bitmap_to_arr32() to convert
a bitmap into a u32. It shoudln't have been a bitmap in the first
place. The reason to use bitmaps is if you have arbitrary number of
bits you want to manage (not two!), or if you rely on the atomicity
guarantees of the bitmap setting and clearing.
The code could use an "atomic_t" and use "atomic_or/andnot()" to set and
clear the bit values, but considering that it then copies the bitmaps
around with "bitmap_to_arr32()" and friends, there clearly cannot be a
lot of atomicity requirements.
So just use a regular integer.
In the process, this avoids the warnings about erroneous use of
bitmap_from_u64() which were triggered on 32-bit architectures when
conversion from a u64 would access two words (and, surprise, surprise,
only one word is needed - and indeed overkill - for a 2-bit bitmap).
That was always problematic, but the compiler seems to notice it and
warn about the invalid pattern only after commit 0a97953fd221 ("lib: add
bitmap_{from,to}_arr64") changed the exact implementation details of
'bitmap_from_u64()', as reported by Sudip Mukherjee and Stephen Rothwell.
Fixes: fe92ee6425a2 ("Bluetooth: hci_core: Rework hci_conn_params flags")
Link: https://lore.kernel.org/all/YpyJ9qTNHJzz0FHY@debian/
Link: https://lore.kernel.org/all/20220606080631.0c3014f2@canb.auug.org.au/
Link: https://lore.kernel.org/all/20220605162537.1604762-1-yury.norov@gmail.com/
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'net/bluetooth/hci_sync.c')
| -rw-r--r-- | net/bluetooth/hci_sync.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index 4d2203c5f1bb..286d6767f017 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -1637,7 +1637,7 @@ static int hci_le_set_privacy_mode_sync(struct hci_dev *hdev, * indicates that LL Privacy has been enabled and * HCI_OP_LE_SET_PRIVACY_MODE is supported. */ - if (!test_bit(HCI_CONN_FLAG_DEVICE_PRIVACY, params->flags)) + if (!(params->flags & HCI_CONN_FLAG_DEVICE_PRIVACY)) return 0; irk = hci_find_irk_by_addr(hdev, ¶ms->addr, params->addr_type); @@ -1666,7 +1666,7 @@ static int hci_le_add_accept_list_sync(struct hci_dev *hdev, /* During suspend, only wakeable devices can be in acceptlist */ if (hdev->suspended && - !test_bit(HCI_CONN_FLAG_REMOTE_WAKEUP, params->flags)) + !(params->flags & HCI_CONN_FLAG_REMOTE_WAKEUP)) return 0; /* Select filter policy to accept all advertising */ @@ -4888,7 +4888,7 @@ static int hci_update_event_filter_sync(struct hci_dev *hdev) hci_clear_event_filter_sync(hdev); list_for_each_entry(b, &hdev->accept_list, list) { - if (!test_bit(HCI_CONN_FLAG_REMOTE_WAKEUP, b->flags)) + if (!(b->flags & HCI_CONN_FLAG_REMOTE_WAKEUP)) continue; bt_dev_dbg(hdev, "Adding event filters for %pMR", &b->bdaddr); |