diff options
| author | Ilpo Järvinen <[email protected]> | 2024-05-07 13:25:16 +0300 |
|---|---|---|
| committer | Bjorn Helgaas <[email protected]> | 2024-05-28 11:14:14 -0500 |
| commit | 903534fa7d30214d8ba840ab1cd9e917e0c88e41 (patch) | |
| tree | c1594c0734bd03d41eb685813e0dae60b8adcf78 | |
| parent | 2700225304e8e4f0f29f2bbb8ad0c112c9666d90 (diff) | |
PCI: Fix resource double counting on remove & rescan
pbus_size_mem() keeps the size of the optional resources in
children_add_size. When calculating the PCI bridge window size,
calculate_memsize() lower bounds size by old_size before adding
children_add_size and performing the window size alignment. This
results in double counting for the resources in children_add_size
because old_size may be based on the previous size of the bridge
window after it has already included children_add_size (that is,
size1 in pbus_size_mem() from an earlier invocation of that
function).
As a result, on repeated remove of the bus & rescan cycles the resource
size keeps increasing when children_add_size is non-zero as can be seen
from this extract:
iomem0: 23fffd00000-23fffdfffff : PCI Bus 0000:03 # 1MiB
iomem1: 20000000000-200001fffff : PCI Bus 0000:03 # 2MiB
iomem2: 20000000000-200002fffff : PCI Bus 0000:03 # 3MiB
iomem3: 20000000000-200003fffff : PCI Bus 0000:03 # 4MiB
iomem4: 20000000000-200004fffff : PCI Bus 0000:03 # 5MiB
Solve the double counting by moving old_size check later in
calculate_memsize() so that children_add_size is already accounted for.
After the patch, the bridge window retains its size as expected:
iomem0: 23fffd00000-23fffdfffff : PCI Bus 0000:03 # 1MiB
iomem1: 20000000000-200000fffff : PCI Bus 0000:03 # 1MiB
iomem2: 20000000000-200000fffff : PCI Bus 0000:03 # 1MiB
Fixes: a4ac9fea016f ("PCI : Calculate right add_size")
Link: https://lore.kernel.org/r/[email protected]
Tested-by: Lidong Wang <[email protected]>
Signed-off-by: Ilpo Järvinen <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Mika Westerberg <[email protected]>
| -rw-r--r-- | drivers/pci/setup-bus.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 909e6a7c3cc3..141d6b31959b 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -829,11 +829,9 @@ static resource_size_t calculate_memsize(resource_size_t size, size = min_size; if (old_size == 1) old_size = 0; - if (size < old_size) - size = old_size; - size = ALIGN(max(size, add_size) + children_add_size, align); - return size; + size = max(size, add_size) + children_add_size; + return ALIGN(max(size, old_size), align); } resource_size_t __weak pcibios_window_alignment(struct pci_bus *bus, |