Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-25 13:41:51 +00:00
Code Issues Packages Projects Releases Wiki Activity

xen-pciback: Allow setting PCI_MSIX_FLAGS_MASKALL too

Browse Source 
When Xen domain configures MSI-X, the usual approach is to enable MSI-X
together with masking all of them via the config space, then fill the
table and only then clear PCI_MSIX_FLAGS_MASKALL. Allow doing this via
QEMU running in a stub domain.

Previously, when changing PCI_MSIX_FLAGS_MASKALL was not allowed, the
whole write was aborted, preventing change to the PCI_MSIX_FLAGS_ENABLE
bit too.

Note the Xen hypervisor intercepts this write anyway, and may keep the
PCI_MSIX_FLAGS_MASKALL bit set if it wishes to. It will store the
guest-requested state and will apply it eventually.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Link: https://lore.kernel.org/r/20221114103110.1519413-1-marmarek@invisiblethingslab.com
Signed-off-by: Juergen Gross <jgross@suse.com>
This commit is contained in:
Marek Marczykowski-Górecki 2022-11-14 11:31:08 +01:00 committed by Juergen Gross
parent da36a2a76b
commit 5e29500eba
1 changed files with 6 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
drivers/xen/xen-pciback/conf_space_capability.c
View File

@ -190,13 +190,16 @@ static const struct config_field caplist_pm[] = {
};
static struct msi_msix_field_config {
u16 enable_bit; /* bit for enabling MSI/MSI-X */
unsigned int int_type; /* interrupt type for exclusiveness check */
u16 enable_bit; /* bit for enabling MSI/MSI-X */
u16 allowed_bits; /* bits allowed to be changed */
unsigned int int_type; /* interrupt type for exclusiveness check */
} msi_field_config = {
.enable_bit = PCI_MSI_FLAGS_ENABLE,
.allowed_bits = PCI_MSI_FLAGS_ENABLE,
.int_type = INTERRUPT_TYPE_MSI,
}, msix_field_config = {
.enable_bit = PCI_MSIX_FLAGS_ENABLE,
.allowed_bits = PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL,
.int_type = INTERRUPT_TYPE_MSIX,
};
@ -229,7 +232,7 @@ static int msi_msix_flags_write(struct pci_dev *dev, int offset, u16 new_value,
return 0;
if (!dev_data->allow_interrupt_control ||
(new_value ^ old_value) & ~field_config->enable_bit)
(new_value ^ old_value) & ~field_config->allowed_bits)
return PCIBIOS_SET_FAILED;
if (new_value & field_config->enable_bit) {