On Wed, Mar 25, 2020 at 05:10:33PM -0500, Bjorn Helgaas wrote:
Hi Kelsey,
On Wed, Mar 25, 2020 at 09:17:08AM -0600, Kelsey Skunberg wrote:
From: Kelsey Skunberg kelsey.skunberg@gmail.com
rename device attribute name arguments 'bus_rescan' and 'dev_rescan' to 'rescan' to avoid breaking userspace applications.
The attribute argument names were changed in the following commits: 8bdfa145f582 ("PCI: sysfs: Define device attributes with DEVICE_ATTR*()") 4e2b79436e4f ("PCI: sysfs: Change DEVICE_ATTR() to DEVICE_ATTR_WO()")
Revert the names used for attributes back to the names used before the above patches were applied. This also requires to change DEVICE_ATTR_WO() to DEVICE_ATTR() and __ATTR().
Note when using DEVICE_ATTR() the attribute is automatically named dev_attr_<name>.attr. To avoid duplicated names between attributes, use __ATTR() instead of DEVICE_ATTR() to a assign a custom attribute name for dev_rescan.
change bus_rescan_store() to dev_bus_rescan_store() to complete matching the names used before the mentioned patches were applied.
Fixes: 8bdfa145f582 ("PCI: sysfs: Define device attributes with DEVICE_ATTR*()") Fixes: 4e2b79436e4f ("PCI: sysfs: Change DEVICE_ATTR() to DEVICE_ATTR_WO()")
Cc: stable stable@vger.kernel.org Signed-off-by: Kelsey Skunberg kelsey.skunberg@gmail.com Reviewed-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
v2 updates: commit log updated to include 'Fixes: *' and Cc: stable to aid commit being backported properly.
drivers/pci/pci-sysfs.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 13f766db0684..667e13d597ff 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -464,7 +464,10 @@ static ssize_t dev_rescan_store(struct device *dev, } return count; } -static DEVICE_ATTR_WO(dev_rescan); +static struct device_attribute dev_rescan_attr = __ATTR(rescan,
0220, NULL,dev_rescan_store);static ssize_t remove_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) @@ -481,9 +484,9 @@ static ssize_t remove_store(struct device *dev, struct device_attribute *attr, static DEVICE_ATTR_IGNORE_LOCKDEP(remove, 0220, NULL, remove_store); -static ssize_t bus_rescan_store(struct device *dev,
struct device_attribute *attr,const char *buf, size_t count)+static ssize_t dev_bus_rescan_store(struct device *dev,
struct device_attribute *attr,const char *buf, size_t count){ unsigned long val; struct pci_bus *bus = to_pci_bus(dev); @@ -501,7 +504,7 @@ static ssize_t bus_rescan_store(struct device *dev, } return count; } -static DEVICE_ATTR_WO(bus_rescan); +static DEVICE_ATTR(rescan, 0220, NULL, dev_bus_rescan_store); #if defined(CONFIG_PM) && defined(CONFIG_ACPI) static ssize_t d3cold_allowed_store(struct device *dev, @@ -641,7 +644,7 @@ static struct attribute *pcie_dev_attrs[] = { }; static struct attribute *pcibus_attrs[] = {
- &dev_attr_bus_rescan.attr,
- &dev_attr_rescan.attr, &dev_attr_cpuaffinity.attr, &dev_attr_cpulistaffinity.attr, NULL,
@@ -1487,7 +1490,7 @@ static umode_t pci_dev_attrs_are_visible(struct kobject *kobj, static struct attribute *pci_dev_hp_attrs[] = { &dev_attr_remove.attr,
- &dev_attr_dev_rescan.attr,
- &dev_rescan_attr.attr, NULL,
};
Thanks for taking care of this! Two questions:
- You supplied permissions of 0220, but DEVICE_ATTR_WO()
uses__ATTR_WO(), which uses 0200. Shouldn't we keep 0200?
- I think the use of __ATTR() for the device side and DEVICE_ATTR()
for the bus side is confusing. Couldn't we accomplish the same thing with a patch like the following (compiled but not tested)?
Bjorn
commit 06094b3fd9f1 ("PCI: sysfs: Revert "rescan" file renames") Author: Kelsey Skunberg kelsey.skunberg@gmail.com Date: Wed Mar 25 09:17:08 2020 -0600
PCI: sysfs: Revert "rescan" file renamesWe changed these sysfs filenames: .../pci_bus/domain:bus/rescan -> .../pci_bus/domain:bus/bus_rescan .../domain:bus:dev.fn/rescan -> .../domain:bus:dev.fn/dev_rescan and Ruslan reported [1] that this broke a userspace application. Revert these name changes so both files are named "rescan" again. The argument to DEVICE_ATTR_WO() determines both the struct device_attribute name and the .store() function name. We have to use __ATTR() so we can specify different .store() functions for the two "rescan" files. [1] https://lore.kernel.org/r/CAB=otbSYozS-ZfxB0nCiNnxcbqxwrHOSYxJJtDKa63KzXbXgp... [bhelgaas: commit log] Fixes: 8bdfa145f582 ("PCI: sysfs: Define device attributes with DEVICE_ATTR*()") Fixes: 4e2b79436e4f ("PCI: sysfs: Change DEVICE_ATTR() to DEVICE_ATTR_WO()") Link: https://lore.kernel.org/r/20200325151708.32612-1-skunberg.kelsey@gmail.com Signed-off-by: Kelsey Skunberg kelsey.skunberg@gmail.com Cc: stable@vger.kernel.org # v5.4+
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 13f766db0684..bf025a2c296d 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -464,7 +464,8 @@ static ssize_t dev_rescan_store(struct device *dev, } return count; } -static DEVICE_ATTR_WO(dev_rescan); +static struct device_attribute dev_attr_dev_rescan = __ATTR(rescan, 0200, NULL,
dev_rescan_store);
Oops, this should just be DEVICE_ATTR(), no need for __ATTR() as this isn't a kobject-only file.
So how about:
static DEVICE_ATTR(rescan, 0200, NULL, dev_rescan_store);
Much smaller :)
Sorry I missed that in the original review.
thanks,
greg k-h