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Dan Williams authored
Commit a1f3e4d6 "libnvdimm, region: update nd_region_available_dpa() for multi-pmem support" reworked blk dpa (DIMM Physical Address) accounting to comprehend multiple pmem namespace allocations aliasing with a given blk-dpa range. The following call trace is a result of failing to account for allocated blk capacity. WARNING: CPU: 1 PID: 2433 at tools/testing/nvdimm/../../../drivers/nvdimm/names 4 size_store+0x6f3/0x930 [libnvdimm] nd_region region5: allocation underrun: 0x0 of 0x1000000 bytes [..] Call Trace: dump_stack+0x86/0xc3 __warn+0xcb/0xf0 warn_slowpath_fmt+0x5f/0x80 size_store+0x6f3/0x930 [libnvdimm] dev_attr_store+0x18/0x30 If a given blk-dpa allocation does not alias with any pmem ranges then the full allocation should be accounted as busy space, not the size of the current pmem contribution to the region. The thinkos that led to this confusion was not realizing that the struct resource management is already guaranteeing no collisions between pmem allocations and blk allocations on the same dimm. Also, we do not try to support blk allocations in aliased pmem holes. This patch also fixes a case where the available blk goes negative. Cc: <stable@vger.kernel.org> Fixes: a1f3e4d6 ("libnvdimm, region: update nd_region_available_dpa() for multi-pmem support"). Reported-by:
Dariusz Dokupil <dariusz.dokupil@intel.com> Reported-by:
Dave Jiang <dave.jiang@intel.com> Reported-by:
Vishal Verma <vishal.l.verma@intel.com> Tested-by:
Dave Jiang <dave.jiang@intel.com> Tested-by:
Vishal Verma <vishal.l.verma@intel.com> Signed-off-by:
Dan Williams <dan.j.williams@intel.com>
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