PCI: fix access of PCI_X_CMD by pcix get and set mmrbc functions (bdc2bda7) · Commits · 戴 / test

An e1000 driver on a system with a PCI-X bus was always being returned a value of 135 from both pcix_get_mmrbc() and pcix_set_mmrbc(). This value reflects an error return of PCIBIOS_BAD_REGISTER_NUMBER from pci_bus_read_config_dword(,, cap + PCI_X_CMD,). This is because for a dword, the following portion of the PCI_OP_READ() macro: if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER; expands to: if (pos & 3) return PCIBIOS_BAD_REGISTER_NUMBER; And is always true for 'cap + PCI_X_CMD', which is 0xe4 + 2 = 0xe6. ('cap' is the result of calling pci_find_capability(, PCI_CAP_ID_PCIX).) The same problem exists for pci_bus_write_config_dword(,, cap + PCI_X_CMD,). In both cases, instead of calling _dword(), _word() should be called. Cc: stable@kernel.org Signed-off-by:

Dean Nelson <dnelson@redhat.com> Signed-off-by:

Jesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/pci.c

+6 −5

Original line number	Diff line number	Diff line
		@@ -2601,13 +2601,13 @@ EXPORT_SYMBOL(pcix_get_max_mmrbc);
		int pcix_get_mmrbc(struct pci_dev *dev)
		{
		int ret, cap;
		u32 cmd;
		u16 cmd;

		cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
		if (!cap)
		return -EINVAL;

		ret = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
		ret = pci_read_config_word(dev, cap + PCI_X_CMD, &cmd);
		if (!ret)
		ret = 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);

		@@ -2627,7 +2627,8 @@ EXPORT_SYMBOL(pcix_get_mmrbc);
		int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
		{
		int cap, err = -EINVAL;
		u32 stat, cmd, v, o;
		u32 stat, v, o;
		u16 cmd;

		if (mmrbc < 512 \|\| mmrbc > 4096 \|\| !is_power_of_2(mmrbc))
		goto out;
		@@ -2645,7 +2646,7 @@ int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
		if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
		return -E2BIG;

		err = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
		err = pci_read_config_word(dev, cap + PCI_X_CMD, &cmd);
		if (err)
		goto out;

		@@ -2657,7 +2658,7 @@ int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)

		cmd &= ~PCI_X_CMD_MAX_READ;
		cmd \|= v << 2;
		err = pci_write_config_dword(dev, cap + PCI_X_CMD, cmd);
		err = pci_write_config_word(dev, cap + PCI_X_CMD, cmd);
		}
		out:
		return err;

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