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author | Ryo Takakura <ryotkkr98@gmail.com> | 2025-02-18 09:08:30 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-04-20 10:15:26 +0200 |
commit | 5c3cfcf0b4bf43530788b08a8eaf7896ec567484 (patch) | |
tree | 4f3bbcdc9d0d68411606cfc41faec6a2d6885a24 /drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | |
parent | 73d2b962503151f7a69cfe28f24185fb96c14915 (diff) |
PCI: vmd: Make vmd_dev::cfg_lock a raw_spinlock_t type
[ Upstream commit 18056a48669a040bef491e63b25896561ee14d90 ]
The access to the PCI config space via pci_ops::read and pci_ops::write is
a low-level hardware access. The functions can be accessed with disabled
interrupts even on PREEMPT_RT. The pci_lock is a raw_spinlock_t for this
purpose.
A spinlock_t becomes a sleeping lock on PREEMPT_RT, so it cannot be
acquired with disabled interrupts. The vmd_dev::cfg_lock is accessed in
the same context as the pci_lock.
Make vmd_dev::cfg_lock a raw_spinlock_t type so it can be used with
interrupts disabled.
This was reported as:
BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48
Call Trace:
rt_spin_lock+0x4e/0x130
vmd_pci_read+0x8d/0x100 [vmd]
pci_user_read_config_byte+0x6f/0xe0
pci_read_config+0xfe/0x290
sysfs_kf_bin_read+0x68/0x90
Signed-off-by: Ryo Takakura <ryotkkr98@gmail.com>
Tested-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Acked-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
[bigeasy: reword commit message]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-off-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/r/20250218080830.ufw3IgyX@linutronix.de
[kwilczynski: commit log]
Signed-off-by: Krzysztof WilczyĆski <kwilczynski@kernel.org>
[bhelgaas: add back report info from
https://lore.kernel.org/lkml/20241218115951.83062-1-ryotkkr98@gmail.com/]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_device.c')
0 files changed, 0 insertions, 0 deletions