Re: [patch V2 19/23] PCI/MSI: Sanitize MSIX table map handling
From: Bjorn Helgaas <helgaas@kernel.org>
Date: 2021-12-07 21:01:49
Also in:
ath11k, linux-hyperv, linux-pci, linuxppc-dev, lkml, sparclinux, xen-devel
On Mon, Dec 06, 2021 at 11:27:54PM +0100, Thomas Gleixner wrote:
Unmapping the MSIX base mapping in the loops which allocate/free MSI desciptors is daft and in the way of allowing runtime expansion of MSI-X descriptors.
s/MSIX/MSI-X/ (subject and first use in commit log) s/desciptors/descriptors/
Store the mapping in struct pci_dev and free it after freeing the MSI-X descriptors. Signed-off-by: Thomas Gleixner <redacted> Tested-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
quoted hunk ↗ jump to hunk
--- drivers/pci/msi/msi.c | 18 ++++++++---------- include/linux/pci.h | 1 + 2 files changed, 9 insertions(+), 10 deletions(-)--- a/drivers/pci/msi/msi.c +++ b/drivers/pci/msi/msi.c@@ -241,14 +241,14 @@ static void free_msi_irqs(struct pci_dev pci_msi_teardown_msi_irqs(dev); list_for_each_entry_safe(entry, tmp, msi_list, list) { - if (entry->pci.msi_attrib.is_msix) { - if (list_is_last(&entry->list, msi_list)) - iounmap(entry->pci.mask_base); - } - list_del(&entry->list); free_msi_entry(entry); } + + if (dev->msix_base) { + iounmap(dev->msix_base); + dev->msix_base = NULL; + } } static void pci_intx_for_msi(struct pci_dev *dev, int enable)@@ -501,10 +501,6 @@ static int msix_setup_entries(struct pci for (i = 0, curmsk = masks; i < nvec; i++) { entry = alloc_msi_entry(&dev->dev, 1, curmsk); if (!entry) { - if (!i) - iounmap(base); - else - free_msi_irqs(dev); /* No enough memory. Don't try again */ ret = -ENOMEM; goto out;@@ -602,12 +598,14 @@ static int msix_capability_init(struct p goto out_disable; } + dev->msix_base = base; + /* Ensure that all table entries are masked. */ msix_mask_all(base, tsize); ret = msix_setup_entries(dev, base, entries, nvec, affd); if (ret) - goto out_disable; + goto out_free; ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX); if (ret) --- a/include/linux/pci.h +++ b/include/linux/pci.h@@ -473,6 +473,7 @@ struct pci_dev { u8 ptm_granularity; #endif #ifdef CONFIG_PCI_MSI + void __iomem *msix_base; const struct attribute_group **msi_irq_groups; #endif struct pci_vpd vpd;