On Thu, Dec 19, 2024 at 10:45:49AM +0900, Ryo Takakura wrote: > PCI config access is locked with pci_lock which is raw_spinlock. > Convert cfg_lock to raw_spinlock so that the lock usage is consistent > for RT kernel. Any movement here? Tested-off-by: Luis Claudio R. Goncalves <lgoncalv@xxxxxxxxxx> Acked-by: Luis Claudio R. Goncalves <lgoncalv@xxxxxxxxxx> Best, Luis > Reported as following: > [ 18.756807] BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 > [ 18.756810] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1617, name: nodedev-init > [ 18.756810] preempt_count: 1, expected: 0 > [ 18.756811] RCU nest depth: 0, expected: 0 > [ 18.756811] INFO: lockdep is turned off. > [ 18.756812] irq event stamp: 0 > [ 18.756812] hardirqs last enabled at (0): [<0000000000000000>] 0x0 > [ 18.756815] hardirqs last disabled at (0): [<ffffffff864f1fe2>] copy_process+0xa62/0x2d90 > [ 18.756819] softirqs last enabled at (0): [<ffffffff864f1fe2>] copy_process+0xa62/0x2d90 > [ 18.756820] softirqs last disabled at (0): [<0000000000000000>] 0x0 > [ 18.756822] CPU: 3 UID: 0 PID: 1617 Comm: nodedev-init Tainted: G W 6.12.1 #11 > [ 18.756823] Tainted: [W]=WARN > [ 18.756824] Hardware name: Dell Inc. Vostro 3710/0K1D6X, BIOS 1.14.0 06/09/2023 > [ 18.756825] Call Trace: > [ 18.756826] <TASK> > [ 18.756827] dump_stack_lvl+0x9b/0xf0 > [ 18.756830] dump_stack+0x10/0x20 > [ 18.756831] __might_resched+0x158/0x230 > [ 18.756833] rt_spin_lock+0x4e/0x130 > [ 18.756837] ? vmd_pci_read+0x8d/0x100 [vmd] > [ 18.756839] vmd_pci_read+0x8d/0x100 [vmd] > [ 18.756840] pci_user_read_config_byte+0x6f/0xe0 > [ 18.756843] pci_read_config+0xfe/0x290 > [ 18.756845] sysfs_kf_bin_read+0x68/0x90 > [ 18.756847] kernfs_fop_read_iter+0xd7/0x200 > [ 18.756850] vfs_read+0x26d/0x360 > [ 18.756853] ksys_read+0x70/0xf0 > [ 18.756855] __x64_sys_read+0x1a/0x20 > [ 18.756857] x64_sys_call+0x1715/0x20d0 > [ 18.756859] do_syscall_64+0x8f/0x170 > [ 18.756861] ? syscall_exit_to_user_mode+0xcd/0x2c0 > [ 18.756863] ? do_syscall_64+0x9b/0x170 > [ 18.756865] entry_SYSCALL_64_after_hwframe+0x76/0x7e > > Signed-off-by: Ryo Takakura <ryotkkr98@xxxxxxxxx> > > --- > > Hi! > > This is same as the first version of the patch as discussed over v2. > > v1: > https://lore.kernel.org/lkml/20241215141321.383144-1-ryotkkr98@xxxxxxxxx/T/ > > Changes since v2: > https://lore.kernel.org/lkml/20241218115951.83062-1-ryotkkr98@xxxxxxxxx/T/ > > - In case if CONFIG_PCI_LOCKLESS_CONFIG is set, vmd_pci_read/write() > still neeed cfg_lock for their serialization. So instead of removing > it, convert it to raw spinlock. > > --- > drivers/pci/controller/vmd.c | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > > diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c > index 9d9596947..94ceec50a 100644 > --- a/drivers/pci/controller/vmd.c > +++ b/drivers/pci/controller/vmd.c > @@ -125,7 +125,7 @@ struct vmd_irq_list { > struct vmd_dev { > struct pci_dev *dev; > > - spinlock_t cfg_lock; > + raw_spinlock_t cfg_lock; > void __iomem *cfgbar; > > int msix_count; > @@ -391,7 +391,7 @@ static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg, > if (!addr) > return -EFAULT; > > - spin_lock_irqsave(&vmd->cfg_lock, flags); > + raw_spin_lock_irqsave(&vmd->cfg_lock, flags); > switch (len) { > case 1: > *value = readb(addr); > @@ -406,7 +406,7 @@ static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg, > ret = -EINVAL; > break; > } > - spin_unlock_irqrestore(&vmd->cfg_lock, flags); > + raw_spin_unlock_irqrestore(&vmd->cfg_lock, flags); > return ret; > } > > @@ -426,7 +426,7 @@ static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg, > if (!addr) > return -EFAULT; > > - spin_lock_irqsave(&vmd->cfg_lock, flags); > + raw_spin_lock_irqsave(&vmd->cfg_lock, flags); > switch (len) { > case 1: > writeb(value, addr); > @@ -444,7 +444,7 @@ static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg, > ret = -EINVAL; > break; > } > - spin_unlock_irqrestore(&vmd->cfg_lock, flags); > + raw_spin_unlock_irqrestore(&vmd->cfg_lock, flags); > return ret; > } > > @@ -1009,7 +1009,7 @@ static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id) > if (features & VMD_FEAT_OFFSET_FIRST_VECTOR) > vmd->first_vec = 1; > > - spin_lock_init(&vmd->cfg_lock); > + raw_spin_lock_init(&vmd->cfg_lock); > pci_set_drvdata(dev, vmd); > err = vmd_enable_domain(vmd, features); > if (err) > -- > 2.34.1 > ---end quoted text---
