Hi Andre,
On 6/21/21 3:04 PM, Andre Przywara wrote:
> On Mon, 21 Jun 2021 10:21:27 +0100
> Alexandru Elisei <alexandru.elisei@xxxxxxx> wrote:
>
>> PCI Express comes with an extended addressing scheme, which directly
>> translated into a bigger device configuration space (256->4096 bytes)
>> and bigger PCI configuration space (16->256 MB), as well as mandatory
>> capabilities (power management [1] and PCI Express capability [2]).
>>
>> However, our virtio PCI implementation implements version 0.9 of the
>> protocol and it still uses transitional PCI device ID's, so we have
>> opted to omit the mandatory PCI Express capabilities. For VFIO, the power
>> management and PCI Express capability are left for a subsequent patch.
>>
>> [1] PCI Express Base Specification Revision 1.1, section 7.6
>> [2] PCI Express Base Specification Revision 1.1, section 7.8
>>
>> Signed-off-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
> Sorry, one thing I missed on the first review:
>
>> ---
>> arm/include/arm-common/kvm-arch.h | 4 ++-
>> arm/pci.c | 2 +-
>> include/kvm/pci.h | 51 ++++++++++++++++++++++++++++---
>> pci.c | 5 +--
>> vfio/pci.c | 26 ++++++++++------
>> 5 files changed, 70 insertions(+), 18 deletions(-)
>>
>> diff --git a/arm/include/arm-common/kvm-arch.h b/arm/include/arm-common/kvm-arch.h
>> index 436b67b843fc..c645ac001bca 100644
>> --- a/arm/include/arm-common/kvm-arch.h
>> +++ b/arm/include/arm-common/kvm-arch.h
>> @@ -49,7 +49,7 @@
>>
>>
>> #define KVM_PCI_CFG_AREA ARM_AXI_AREA
>> -#define ARM_PCI_CFG_SIZE (1ULL << 24)
>> +#define ARM_PCI_CFG_SIZE (1ULL << 28)
>> #define KVM_PCI_MMIO_AREA (KVM_PCI_CFG_AREA + ARM_PCI_CFG_SIZE)
>> #define ARM_PCI_MMIO_SIZE (ARM_MEMORY_AREA - \
>> (ARM_AXI_AREA + ARM_PCI_CFG_SIZE))
>> @@ -77,6 +77,8 @@
>>
>> #define VIRTIO_RING_ENDIAN (VIRTIO_ENDIAN_LE | VIRTIO_ENDIAN_BE)
>>
>> +#define ARCH_HAS_PCI_EXP 1
>> +
>> static inline bool arm_addr_in_ioport_region(u64 phys_addr)
>> {
>> u64 limit = KVM_IOPORT_AREA + ARM_IOPORT_SIZE;
>> diff --git a/arm/pci.c b/arm/pci.c
>> index ed325fa4a811..2251f627d8b5 100644
>> --- a/arm/pci.c
>> +++ b/arm/pci.c
>> @@ -62,7 +62,7 @@ void pci__generate_fdt_nodes(void *fdt)
>> _FDT(fdt_property_cell(fdt, "#address-cells", 0x3));
>> _FDT(fdt_property_cell(fdt, "#size-cells", 0x2));
>> _FDT(fdt_property_cell(fdt, "#interrupt-cells", 0x1));
>> - _FDT(fdt_property_string(fdt, "compatible", "pci-host-cam-generic"));
>> + _FDT(fdt_property_string(fdt, "compatible", "pci-host-ecam-generic"));
>> _FDT(fdt_property(fdt, "dma-coherent", NULL, 0));
>>
>> _FDT(fdt_property(fdt, "bus-range", bus_range, sizeof(bus_range)));
>> diff --git a/include/kvm/pci.h b/include/kvm/pci.h
>> index bf81323d83b7..42d9e1c5645f 100644
>> --- a/include/kvm/pci.h
>> +++ b/include/kvm/pci.h
>> @@ -10,6 +10,7 @@
>> #include "kvm/devices.h"
>> #include "kvm/msi.h"
>> #include "kvm/fdt.h"
>> +#include "kvm/kvm-arch.h"
>>
>> #define pci_dev_err(pci_hdr, fmt, ...) \
>> pr_err("[%04x:%04x] " fmt, pci_hdr->vendor_id, pci_hdr->device_id, ##__VA_ARGS__)
>> @@ -32,10 +33,49 @@
>> #define PCI_CONFIG_BUS_FORWARD 0xcfa
>> #define PCI_IO_SIZE 0x100
>> #define PCI_IOPORT_START 0x6200
>> -#define PCI_CFG_SIZE (1ULL << 24)
>>
>> struct kvm;
>>
>> +/*
>> + * On some distributions, pci_regs.h doesn't define PCI_CFG_SPACE_SIZE and
>> + * PCI_CFG_SPACE_EXP_SIZE, so we define our own.
>> + */
>> +#define PCI_CFG_SIZE_LEGACY (1ULL << 24)
>> +#define PCI_DEV_CFG_SIZE_LEGACY 256
>> +#define PCI_CFG_SIZE_EXTENDED (1ULL << 28)
>> +#define PCI_DEV_CFG_SIZE_EXTENDED 4096
>> +
>> +#ifdef ARCH_HAS_PCI_EXP
>> +#define PCI_CFG_SIZE PCI_CFG_SIZE_EXTENDED
>> +#define PCI_DEV_CFG_SIZE PCI_DEV_CFG_SIZE_EXTENDED
>> +
>> +union pci_config_address {
>> + struct {
>> +#if __BYTE_ORDER == __LITTLE_ENDIAN
>> + unsigned reg_offset : 2; /* 1 .. 0 */
>> + unsigned register_number : 10; /* 11 .. 2 */
>> + unsigned function_number : 3; /* 14 .. 12 */
>> + unsigned device_number : 5; /* 19 .. 15 */
>> + unsigned bus_number : 8; /* 27 .. 20 */
>> + unsigned reserved : 3; /* 30 .. 28 */
>> + unsigned enable_bit : 1; /* 31 */
>> +#else
>> + unsigned enable_bit : 1; /* 31 */
>> + unsigned reserved : 3; /* 30 .. 28 */
>> + unsigned bus_number : 8; /* 27 .. 20 */
>> + unsigned device_number : 5; /* 19 .. 15 */
>> + unsigned function_number : 3; /* 14 .. 12 */
>> + unsigned register_number : 10; /* 11 .. 2 */
>> + unsigned reg_offset : 2; /* 1 .. 0 */
>> +#endif
>> + };
>> + u32 w;
>> +};
>> +
>> +#else
>> +#define PCI_CFG_SIZE PCI_CFG_SIZE_LEGACY
>> +#define PCI_DEV_CFG_SIZE PCI_DEV_CFG_SIZE_LEGACY
>> +
>> union pci_config_address {
>> struct {
>> #if __BYTE_ORDER == __LITTLE_ENDIAN
>> @@ -58,6 +98,9 @@ union pci_config_address {
>> };
>> u32 w;
>> };
>> +#endif /* ARCH_HAS_PCI_EXP */
>> +
>> +#define PCI_DEV_CFG_MASK (PCI_DEV_CFG_SIZE - 1)
>>
>> struct msix_table {
>> struct msi_msg msg;
>> @@ -110,14 +153,12 @@ typedef int (*bar_deactivate_fn_t)(struct kvm *kvm,
>> int bar_num, void *data);
>>
>> #define PCI_BAR_OFFSET(b) (offsetof(struct pci_device_header, bar[b]))
>> -#define PCI_DEV_CFG_SIZE 256
>> -#define PCI_DEV_CFG_MASK (PCI_DEV_CFG_SIZE - 1)
>>
>> struct pci_config_operations {
>> void (*write)(struct kvm *kvm, struct pci_device_header *pci_hdr,
>> - u8 offset, void *data, int sz);
>> + u16 offset, void *data, int sz);
>> void (*read)(struct kvm *kvm, struct pci_device_header *pci_hdr,
>> - u8 offset, void *data, int sz);
>> + u16 offset, void *data, int sz);
>> };
>>
>> struct pci_device_header {
>> diff --git a/pci.c b/pci.c
>> index d6da79e0a56a..e593033164c1 100644
>> --- a/pci.c
>> +++ b/pci.c
>> @@ -353,7 +353,8 @@ static void pci_config_bar_wr(struct kvm *kvm,
>> void pci__config_wr(struct kvm *kvm, union pci_config_address addr, void *data, int size)
>> {
>> void *base;
>> - u8 bar, offset;
>> + u8 bar;
>> + u16 offset;
>> struct pci_device_header *pci_hdr;
>> u8 dev_num = addr.device_number;
>> u32 value = 0;
>> @@ -392,7 +393,7 @@ void pci__config_wr(struct kvm *kvm, union pci_config_address addr, void *data,
>>
>> void pci__config_rd(struct kvm *kvm, union pci_config_address addr, void *data, int size)
>> {
>> - u8 offset;
>> + u16 offset;
>> struct pci_device_header *pci_hdr;
>> u8 dev_num = addr.device_number;
>>
>> diff --git a/vfio/pci.c b/vfio/pci.c
>> index 49ecd12a38cd..6a4204634e71 100644
>> --- a/vfio/pci.c
>> +++ b/vfio/pci.c
>> @@ -313,7 +313,7 @@ out_unlock:
>> }
>>
>> static void vfio_pci_msix_cap_write(struct kvm *kvm,
>> - struct vfio_device *vdev, u8 off,
>> + struct vfio_device *vdev, u16 off,
>> void *data, int sz)
>> {
>> struct vfio_pci_device *pdev = &vdev->pci;
>> @@ -345,7 +345,7 @@ static void vfio_pci_msix_cap_write(struct kvm *kvm,
>> }
>>
>> static int vfio_pci_msi_vector_write(struct kvm *kvm, struct vfio_device *vdev,
>> - u8 off, u8 *data, u32 sz)
>> + u16 off, u8 *data, u32 sz)
>> {
>> size_t i;
>> u32 mask = 0;
>> @@ -393,7 +393,7 @@ static int vfio_pci_msi_vector_write(struct kvm *kvm, struct vfio_device *vdev,
>> }
>>
>> static void vfio_pci_msi_cap_write(struct kvm *kvm, struct vfio_device *vdev,
>> - u8 off, u8 *data, u32 sz)
>> + u16 off, u8 *data, u32 sz)
>> {
>> u8 ctrl;
>> struct msi_msg msg;
>> @@ -553,7 +553,7 @@ out:
>> }
>>
>> static void vfio_pci_cfg_read(struct kvm *kvm, struct pci_device_header *pci_hdr,
>> - u8 offset, void *data, int sz)
>> + u16 offset, void *data, int sz)
>> {
>> struct vfio_region_info *info;
>> struct vfio_pci_device *pdev;
>> @@ -571,7 +571,7 @@ static void vfio_pci_cfg_read(struct kvm *kvm, struct pci_device_header *pci_hdr
>> }
>>
>> static void vfio_pci_cfg_write(struct kvm *kvm, struct pci_device_header *pci_hdr,
>> - u8 offset, void *data, int sz)
>> + u16 offset, void *data, int sz)
>> {
>> struct vfio_region_info *info;
>> struct vfio_pci_device *pdev;
>> @@ -658,15 +658,17 @@ static int vfio_pci_parse_caps(struct vfio_device *vdev)
>> {
>> int ret;
>> size_t size;
>> - u8 pos, next;
>> + u16 pos, next;
>> struct pci_cap_hdr *cap;
>> - u8 virt_hdr[PCI_DEV_CFG_SIZE];
>> + u8 *virt_hdr;
>> struct vfio_pci_device *pdev = &vdev->pci;
>>
>> if (!(pdev->hdr.status & PCI_STATUS_CAP_LIST))
>> return 0;
>>
>> - memset(virt_hdr, 0, PCI_DEV_CFG_SIZE);
>> + virt_hdr = calloc(1, PCI_DEV_CFG_SIZE);
>> + if (!virt_hdr)
>> + return -ENOMEM;
> This will leak if the function returns with an error, due to
> vfio_pci_add_cap() calls failing.
> The easiest way out is probably initialising ret = 0 and using "goto
> out;", I guess.
I don't understand what you mean, can you elaborate?
>From what I can tell, the function doesn't do any assignment before this point, so
I don't know what will leak. vfio_pci_add_cap() calls are skipped entirely if the
function returns early here, so I don't see how they can fail.
Thanks,
Alex
>
> Cheers,
> Andre
>
>
>
>>
>> pos = pdev->hdr.capabilities & ~3;
>>
>> @@ -702,6 +704,8 @@ static int vfio_pci_parse_caps(struct vfio_device *vdev)
>> size = PCI_DEV_CFG_SIZE - PCI_STD_HEADER_SIZEOF;
>> memcpy((void *)&pdev->hdr + pos, virt_hdr + pos, size);
>>
>> + free(virt_hdr);
>> +
>> return 0;
>> }
>>
>> @@ -812,7 +816,11 @@ static int vfio_pci_fixup_cfg_space(struct vfio_device *vdev)
>>
>> /* Install our fake Configuration Space */
>> info = &vdev->regions[VFIO_PCI_CONFIG_REGION_INDEX].info;
>> - hdr_sz = PCI_DEV_CFG_SIZE;
>> + /*
>> + * We don't touch the extended configuration space, let's be cautious
>> + * and not overwrite it all with zeros, or bad things might happen.
>> + */
>> + hdr_sz = PCI_DEV_CFG_SIZE_LEGACY;
>> if (pwrite(vdev->fd, &pdev->hdr, hdr_sz, info->offset) != hdr_sz) {
>> vfio_dev_err(vdev, "failed to write %zd bytes to Config Space",
>> hdr_sz);
