Re: [PATCH] PCI: hv: Fix the definiton of vector in hv_compose_msi_msg()

From: Bjorn Helgaas
Date: Mon Aug 15 2022 - 20:34:08 EST


s/definiton/definition/ in subject
(only if you have other occasion to repost this)

On Mon, Aug 15, 2022 at 11:55:05AM -0700, Dexuan Cui wrote:
> The local variable 'vector' must be u32 rather than u8: see the
> struct hv_msi_desc3.
>
> 'vector_count' should be u16 rather than u8: see struct hv_msi_desc,
> hv_msi_desc2 and hv_msi_desc3.
>
> Fixes: a2bad844a67b ("PCI: hv: Fix interrupt mapping for multi-MSI")
> Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
> Cc: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx>
> Cc: Carl Vanderlip <quic_carlv@xxxxxxxxxxx>

Looks like Wei has been applying most changes to pci-hyperv.c, so I
assume the same will happen here.

> ---
>
> The patch should be appplied after the earlier patch:
> [PATCH] PCI: hv: Only reuse existing IRTE allocation for Multi-MSI
> https://lwn.net/ml/linux-kernel/20220804025104.15673-1-decui%40microsoft.com/
>
> drivers/pci/controller/pci-hyperv.c | 9 +++++----
> 1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
> index 65d0dab25deb..53580899c859 100644
> --- a/drivers/pci/controller/pci-hyperv.c
> +++ b/drivers/pci/controller/pci-hyperv.c
> @@ -1614,7 +1614,7 @@ static void hv_pci_compose_compl(void *context, struct pci_response *resp,
>
> static u32 hv_compose_msi_req_v1(
> struct pci_create_interrupt *int_pkt, struct cpumask *affinity,
> - u32 slot, u8 vector, u8 vector_count)
> + u32 slot, u8 vector, u16 vector_count)
> {
> int_pkt->message_type.type = PCI_CREATE_INTERRUPT_MESSAGE;
> int_pkt->wslot.slot = slot;
> @@ -1642,7 +1642,7 @@ static int hv_compose_msi_req_get_cpu(struct cpumask *affinity)
>
> static u32 hv_compose_msi_req_v2(
> struct pci_create_interrupt2 *int_pkt, struct cpumask *affinity,
> - u32 slot, u8 vector, u8 vector_count)
> + u32 slot, u8 vector, u16 vector_count)
> {
> int cpu;
>
> @@ -1661,7 +1661,7 @@ static u32 hv_compose_msi_req_v2(
>
> static u32 hv_compose_msi_req_v3(
> struct pci_create_interrupt3 *int_pkt, struct cpumask *affinity,
> - u32 slot, u32 vector, u8 vector_count)
> + u32 slot, u32 vector, u16 vector_count)
> {
> int cpu;
>
> @@ -1702,7 +1702,8 @@ static void hv_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
> struct tran_int_desc *int_desc;
> struct msi_desc *msi_desc;
> bool multi_msi;
> - u8 vector, vector_count;
> + u32 vector; /* Must be u32: see the struct hv_msi_desc3 */
> + u16 vector_count;
> struct {
> struct pci_packet pci_pkt;
> union {
> --
> 2.25.1
>