Hi Heiner, On Sun, 05 Sep 2021 17:59:42 +0200, Heiner Kallweit wrote: > As pointed out by Andy in [0] using a local mutex here isn't strictly > wrong but not sufficient. We should hold the PCI rescan lock for P2SB > operations. > > [0] https://www.spinics.net/lists/linux-i2c/msg52717.html > > Fixes: 1a987c69ce2c ("i2c: i801: make p2sb_spinlock a mutex") > Reported-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx> > Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx> > --- > drivers/i2c/busses/i2c-i801.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c > index 89ae78ef1..1f929e6c3 100644 > --- a/drivers/i2c/busses/i2c-i801.c > +++ b/drivers/i2c/busses/i2c-i801.c > @@ -1493,7 +1493,6 @@ static struct platform_device * > i801_add_tco_spt(struct i801_priv *priv, struct pci_dev *pci_dev, > struct resource *tco_res) > { > - static DEFINE_MUTEX(p2sb_mutex); > struct resource *res; > unsigned int devfn; > u64 base64_addr; > @@ -1506,7 +1505,7 @@ i801_add_tco_spt(struct i801_priv *priv, struct pci_dev *pci_dev, > * enumerated by the PCI subsystem, so we need to unhide/hide it > * to lookup the P2SB BAR. > */ > - mutex_lock(&p2sb_mutex); > + pci_lock_rescan_remove(); > > devfn = PCI_DEVFN(PCI_SLOT(pci_dev->devfn), 1); > > @@ -1524,7 +1523,7 @@ i801_add_tco_spt(struct i801_priv *priv, struct pci_dev *pci_dev, > /* Hide the P2SB device, if it was hidden before */ > if (hidden) > pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, hidden); > - mutex_unlock(&p2sb_mutex); > + pci_unlock_rescan_remove(); > > res = &tco_res[1]; > if (pci_dev->device == PCI_DEVICE_ID_INTEL_DNV_SMBUS) Looks good to me. Reviewed-by: Jean Delvare <jdelvare@xxxxxxx> -- Jean Delvare SUSE L3 Support
