Re: [PATCH v2] ide: pci: free PCI BARs on initialization failure

From: Bjorn Helgaas
Date: Tue Oct 03 2017 - 15:14:15 EST

[+cc linux-pci]

On Tue, Oct 03, 2017 at 02:17:13PM +0200, Bartlomiej Zolnierkiewicz wrote:
> Recent pci_assign_irq() changes uncovered a problem with missing
> freeing of PCI BARs on PCI IDE host initialization failure:
>
> ide0: disabled, no IRQ
> ide0: failed to initialize IDE interface
> ide0: disabling port
> cmd64x 0000:00:02.0: IDE controller (0x1095:0x0646 rev 0x07)
> CMD64x_IDE 0000:00:02.0: BAR 0: can't reserve [io 0x8050-0x8057]
> cmd64x 0000:00:02.0: can't reserve resources
> CMD64x_IDE: probe of 0000:00:02.0 failed with error -16
>
> Fix the problem by adding missing freeing of PCI BARs to
> ide_setup_pci_controller() and ide_pci_init_two().
>
> Link: http://lkml.kernel.org/r/32ec730f-c1b0-5584-cd35-f8a809122b96@xxxxxxxxxxxx
> Reported-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Cc: Richard Henderson <rth@xxxxxxxxxxx>
> Cc: Ivan Kokshaysky <ink@xxxxxxxxxxxxxxxxxxxx>
> Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
> Cc: Matt Turner <mattst88@xxxxxxxxx>
> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>

Applied with Guenter's tested-by to for-linus for v4.14, thanks!

> ---
> This should fix problem with reserving PCI resources on a secondary
> PCI device probe attempt (please test when pci_assign_irq() fix is
> not present and "[PATCH] ide: add missing hwif->portdev freeing on
> hwif_init() failure" is applied).
>
> v2:
> - Added missing 'goto out;' in ide_setup_pci_controller()
>
> drivers/ide/setup-pci.c | 63 ++++++++++++++++++++++++++++++------------------
> 1 file changed, 40 insertions(+), 23 deletions(-)
>
> Index: b/drivers/ide/setup-pci.c
> ===================================================================
> --- a/drivers/ide/setup-pci.c 2017-10-03 14:13:02.391779813 +0200
> +++ b/drivers/ide/setup-pci.c 2017-10-03 14:13:59.051779867 +0200
> @@ -179,6 +179,7 @@ EXPORT_SYMBOL_GPL(ide_setup_pci_noise);
> /**
> * ide_pci_enable - do PCI enables
> * @dev: PCI device
> + * @bars: PCI BARs mask
> * @d: IDE port info
> *
> * Enable the IDE PCI device. We attempt to enable the device in full
> @@ -189,9 +190,10 @@ EXPORT_SYMBOL_GPL(ide_setup_pci_noise);
> * Returns zero on success or an error code
> */
>
> -static int ide_pci_enable(struct pci_dev *dev, const struct ide_port_info *d)
> +static int ide_pci_enable(struct pci_dev *dev, int bars,
> + const struct ide_port_info *d)
> {
> - int ret, bars;
> + int ret;
>
> if (pci_enable_device(dev)) {
> ret = pci_enable_device_io(dev);
> @@ -216,18 +218,6 @@ static int ide_pci_enable(struct pci_dev
> goto out;
> }
>
> - if (d->host_flags & IDE_HFLAG_SINGLE)
> - bars = (1 << 2) - 1;
> - else
> - bars = (1 << 4) - 1;
> -
> - if ((d->host_flags & IDE_HFLAG_NO_DMA) == 0) {
> - if (d->host_flags & IDE_HFLAG_CS5520)
> - bars |= (1 << 2);
> - else
> - bars |= (1 << 4);
> - }
> -
> ret = pci_request_selected_regions(dev, bars, d->name);
> if (ret < 0)
> printk(KERN_ERR "%s %s: can't reserve resources\n",
> @@ -403,6 +393,7 @@ int ide_hwif_setup_dma(ide_hwif_t *hwif,
> /**
> * ide_setup_pci_controller - set up IDE PCI
> * @dev: PCI device
> + * @bars: PCI BARs mask
> * @d: IDE port info
> * @noisy: verbose flag
> *
> @@ -411,7 +402,7 @@ int ide_hwif_setup_dma(ide_hwif_t *hwif,
> * and enables it if need be
> */
>
> -static int ide_setup_pci_controller(struct pci_dev *dev,
> +static int ide_setup_pci_controller(struct pci_dev *dev, int bars,
> const struct ide_port_info *d, int noisy)
> {
> int ret;
> @@ -420,7 +411,7 @@ static int ide_setup_pci_controller(stru
> if (noisy)
> ide_setup_pci_noise(dev, d);
>
> - ret = ide_pci_enable(dev, d);
> + ret = ide_pci_enable(dev, bars, d);
> if (ret < 0)
> goto out;
>
> @@ -428,16 +419,20 @@ static int ide_setup_pci_controller(stru
> if (ret < 0) {
> printk(KERN_ERR "%s %s: error accessing PCI regs\n",
> d->name, pci_name(dev));
> - goto out;
> + goto out_free_bars;
> }
> if (!(pcicmd & PCI_COMMAND_IO)) { /* is device disabled? */
> ret = ide_pci_configure(dev, d);
> if (ret < 0)
> - goto out;
> + goto out_free_bars;
> printk(KERN_INFO "%s %s: device enabled (Linux)\n",
> d->name, pci_name(dev));
> }
>
> + goto out;
> +
> +out_free_bars:
> + pci_release_selected_regions(dev, bars);
> out:
> return ret;
> }
> @@ -540,13 +535,28 @@ int ide_pci_init_two(struct pci_dev *dev
> {
> struct pci_dev *pdev[] = { dev1, dev2 };
> struct ide_host *host;
> - int ret, i, n_ports = dev2 ? 4 : 2;
> + int ret, i, n_ports = dev2 ? 4 : 2, bars;
> struct ide_hw hw[4], *hws[] = { NULL, NULL, NULL, NULL };
>
> + if (d->host_flags & IDE_HFLAG_SINGLE)
> + bars = (1 << 2) - 1;
> + else
> + bars = (1 << 4) - 1;
> +
> + if ((d->host_flags & IDE_HFLAG_NO_DMA) == 0) {
> + if (d->host_flags & IDE_HFLAG_CS5520)
> + bars |= (1 << 2);
> + else
> + bars |= (1 << 4);
> + }
> +
> for (i = 0; i < n_ports / 2; i++) {
> - ret = ide_setup_pci_controller(pdev[i], d, !i);
> - if (ret < 0)
> + ret = ide_setup_pci_controller(pdev[i], bars, d, !i);
> + if (ret < 0) {
> + if (i == 1)
> + pci_release_selected_regions(pdev[0], bars);
> goto out;
> + }
>
> ide_pci_setup_ports(pdev[i], d, &hw[i*2], &hws[i*2]);
> }
> @@ -554,7 +564,7 @@ int ide_pci_init_two(struct pci_dev *dev
> host = ide_host_alloc(d, hws, n_ports);
> if (host == NULL) {
> ret = -ENOMEM;
> - goto out;
> + goto out_free_bars;
> }
>
> host->dev[0] = &dev1->dev;
> @@ -576,7 +586,7 @@ int ide_pci_init_two(struct pci_dev *dev
> * do_ide_setup_pci_device() on the first device!
> */
> if (ret < 0)
> - goto out;
> + goto out_free_bars;
>
> /* fixup IRQ */
> if (ide_pci_is_in_compatibility_mode(pdev[i])) {
> @@ -589,6 +599,13 @@ int ide_pci_init_two(struct pci_dev *dev
> ret = ide_host_register(host, d, hws);
> if (ret)
> ide_host_free(host);
> + else
> + goto out;
> +
> +out_free_bars:
> + i = n_ports / 2;
> + while (i--)
> + pci_release_selected_regions(pdev[i], bars);
> out:
> return ret;
> }
>