On Mon, Dec 08, 2025 at 04:18:15PM +0800, Jiqian Chen wrote: > When MSI-X initialization fails, vPCI hides the capability, but > removing handlers and datas won't be performed until the device is > deassigned. So, implement MSI-X cleanup hook that will be called > to cleanup MSI-X related handlers and free it's associated data when > initialization fails. > > Since cleanup function of MSI-X is implemented, delete the open-code > in vpci_deassign_device(). > > Signed-off-by: Jiqian Chen <[email protected]> > --- > cc: "Roger Pau Monné" <[email protected]> > --- > v11->v12 changes: > * In cleanup_msix(), move check "if ( !hide )" above vpci_remove_registers(). > * Remove the check "!pdev->msix_pos" since current callers already do that. > > v10->v11 changes: > * Move calling all cleanup hook in vpci_deassign_device() out of this patch. > * Add hide parameter to cleanup_msix(). > * Check hide, if it is false, return directly instead of letting ctrl RO. > > v9->v10 changes: > * Call all cleanup hook in vpci_deassign_device() instead of cleanup_msix(). > > v8->v9 changes: > * Modify commit message. > * Call cleanup_msix() in vpci_deassign_device() to remove the open-code to > cleanup msix datas. > * In cleanup_msix(), move "list_del(&vpci->msix->next);" above for loop of > iounmap msix tables. > > v7->v8 changes: > * Given the code in vpci_remove_registers() an error in the removal of > registers would likely imply memory corruption, at which point it's > best to fully disable the device. So, Rollback the last two modifications > of v7. > > v6->v7 changes: > * Change the pointer parameter of cleanup_msix() to be const. > * When vpci_remove_registers() in cleanup_msix() fails, not to return > directly, instead try to free msix and re-add ctrl handler. > * Pass pdev->vpci into vpci_add_register() instead of pdev->vpci->msix in > init_msix() since we need that every handler realize that msix is NULL > when msix is freed but handlers are still in there. > > v5->v6 changes: > * Change the logic to add dummy handler when !vpci->msix in cleanup_msix(). > > v4->v5 changes: > * Change definition "static void cleanup_msix" to "static int cf_check > cleanup_msix" > since cleanup hook is changed to be int. > * Add a read-only register for MSIX Control Register in the end of > cleanup_msix(). > > v3->v4 changes: > * Change function name from fini_msix() to cleanup_msix(). > * Change to use XFREE to free vpci->msix. > * In cleanup function, change the sequence of check and remove action > according to > init_msix(). > > v2->v3 changes: > * Remove unnecessary clean operations in fini_msix(). > > v1->v2 changes: > new patch. > > Best regards, > Jiqian Chen. > --- > xen/drivers/vpci/msix.c | 44 ++++++++++++++++++++++++++++++++++++++++- > xen/drivers/vpci/vpci.c | 8 -------- > 2 files changed, 43 insertions(+), 9 deletions(-) > > diff --git a/xen/drivers/vpci/msix.c b/xen/drivers/vpci/msix.c > index 032e471bb1c0..8dcf2cf9d598 100644 > --- a/xen/drivers/vpci/msix.c > +++ b/xen/drivers/vpci/msix.c > @@ -656,6 +656,48 @@ int vpci_make_msix_hole(const struct pci_dev *pdev) > return 0; > } > > +static int cf_check cleanup_msix(const struct pci_dev *pdev, bool hide) > +{ > + int rc; > + struct vpci *vpci = pdev->vpci; > + const unsigned int msix_pos = pdev->msix_pos; > + > + if ( vpci->msix ) > + { > + list_del(&vpci->msix->next); > + for ( unsigned int i = 0; i < ARRAY_SIZE(vpci->msix->table); i++ ) > + if ( vpci->msix->table[i] ) > + iounmap(vpci->msix->table[i]); > + > + XFREE(vpci->msix); > + } > + > + if ( !hide ) > + return 0; > + > + rc = vpci_remove_registers(vpci, msix_control_reg(msix_pos), 2); > + if ( rc ) > + { > + printk(XENLOG_ERR "%pd %pp: fail to remove MSIX handlers rc=%d\n", > + pdev->domain, &pdev->sbdf, rc); > + ASSERT_UNREACHABLE(); > + return rc; > + } > + > + /* > + * The driver may not traverse the capability list and think device > + * supports MSIX by default. So here let the control register of MSIX > + * be Read-Only is to ensure MSIX disabled. > + */ > + rc = vpci_add_register(vpci, vpci_hw_read16, NULL, > + msix_control_reg(msix_pos), 2, NULL); > + if ( rc ) > + printk(XENLOG_ERR "%pd %pp: fail to add MSIX ctrl handler rc=%d\n", > + pdev->domain, &pdev->sbdf, rc);
Like the previous patch, I don't think this last bit is relevant for domUs? Only the hardware domain needs to have the control register explicitly handled. I don't mind adjusting at commit if we agree. Reviewed-by: Roger Pau Monné <[email protected]> Thanks, Roger.
