6.9-stable review patch. If anyone has any objections, please let me know.
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From: Vishal Verma vishal.l.verma@intel.com
[ Upstream commit c14c647bbe23fd96f6bffcc122b9c6c8c46c7928 ]
Patch series "dax/bus.c: Fixups for dax-bus locking", v3.
Commit Fixes: c05ae9d85b47 ("dax/bus.c: replace driver-core lock usage by a local rwsem") introduced a few problems that this series aims to fix. Add back device_lock() where it was correctly used (during device manipulation operations), remove conditional locking in unregister_dax_dev() and unregister_dax_mapping(), use non-interruptible versions of rwsem locks when not called from a user process, and fix up a write vs. read usage of an rwsem.
This patch (of 4):
In [1], Dan points out that all of the WARN_ON_ONCE() usage in the referenced patch should be replaced with lockdep_assert_held, or lockdep_held_assert_write(). Replace these as appropriate.
Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-0-e3dcd755774c@intel.... Link: https://lore.kernel.org/r/65f0b5ef41817_aa222941a@dwillia2-mobl3.amr.corp.in... [1] Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-1-e3dcd755774c@intel.... Fixes: c05ae9d85b47 ("dax/bus.c: replace driver-core lock usage by a local rwsem") Signed-off-by: Vishal Verma vishal.l.verma@intel.com Reported-by: Dan Williams dan.j.williams@intel.com Reviewed-by: Dan Williams dan.j.williams@intel.com Cc: Alison Schofield alison.schofield@intel.com Cc: Dave Jiang dave.jiang@intel.com Cc: Vishal Verma vishal.l.verma@intel.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/dax/bus.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 797e1ebff2997..7924dd542a139 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -192,7 +192,7 @@ static u64 dev_dax_size(struct dev_dax *dev_dax) u64 size = 0; int i;
- WARN_ON_ONCE(!rwsem_is_locked(&dax_dev_rwsem)); + lockdep_assert_held(&dax_dev_rwsem);
for (i = 0; i < dev_dax->nr_range; i++) size += range_len(&dev_dax->ranges[i].range); @@ -302,7 +302,7 @@ static unsigned long long dax_region_avail_size(struct dax_region *dax_region) resource_size_t size = resource_size(&dax_region->res); struct resource *res;
- WARN_ON_ONCE(!rwsem_is_locked(&dax_region_rwsem)); + lockdep_assert_held(&dax_region_rwsem);
for_each_dax_region_resource(dax_region, res) size -= resource_size(res); @@ -447,7 +447,7 @@ static void trim_dev_dax_range(struct dev_dax *dev_dax) struct range *range = &dev_dax->ranges[i].range; struct dax_region *dax_region = dev_dax->region;
- WARN_ON_ONCE(!rwsem_is_locked(&dax_region_rwsem)); + lockdep_assert_held_write(&dax_region_rwsem); dev_dbg(&dev_dax->dev, "delete range[%d]: %#llx:%#llx\n", i, (unsigned long long)range->start, (unsigned long long)range->end); @@ -507,7 +507,7 @@ static int __free_dev_dax_id(struct dev_dax *dev_dax) struct dax_region *dax_region; int rc = dev_dax->id;
- WARN_ON_ONCE(!rwsem_is_locked(&dax_dev_rwsem)); + lockdep_assert_held_write(&dax_dev_rwsem);
if (!dev_dax->dyn_id || dev_dax->id < 0) return -1; @@ -713,7 +713,7 @@ static void __unregister_dax_mapping(void *data)
dev_dbg(dev, "%s\n", __func__);
- WARN_ON_ONCE(!rwsem_is_locked(&dax_region_rwsem)); + lockdep_assert_held_write(&dax_region_rwsem);
dev_dax->ranges[mapping->range_id].mapping = NULL; mapping->range_id = -1; @@ -830,7 +830,7 @@ static int devm_register_dax_mapping(struct dev_dax *dev_dax, int range_id) struct device *dev; int rc;
- WARN_ON_ONCE(!rwsem_is_locked(&dax_region_rwsem)); + lockdep_assert_held_write(&dax_region_rwsem);
if (dev_WARN_ONCE(&dev_dax->dev, !dax_region->dev->driver, "region disabled\n")) @@ -876,7 +876,7 @@ static int alloc_dev_dax_range(struct dev_dax *dev_dax, u64 start, struct resource *alloc; int i, rc;
- WARN_ON_ONCE(!rwsem_is_locked(&dax_region_rwsem)); + lockdep_assert_held_write(&dax_region_rwsem);
/* handle the seed alloc special case */ if (!size) { @@ -935,7 +935,7 @@ static int adjust_dev_dax_range(struct dev_dax *dev_dax, struct resource *res, r struct device *dev = &dev_dax->dev; int rc;
- WARN_ON_ONCE(!rwsem_is_locked(&dax_region_rwsem)); + lockdep_assert_held_write(&dax_region_rwsem);
if (dev_WARN_ONCE(dev, !size, "deletion is handled by dev_dax_shrink\n")) return -EINVAL;