Re: [PATCH v5 11/21] KVM: s390: pci: do initial setup for AEN interpretation

Christian Borntraeger
2022-04-14T07:20:47Z

Am 04.04.22 um 19:43 schrieb Matthew Rosato:
> Initial setup for Adapter Event Notification Interpretation for zPCI
> passthrough devices. Specifically, allocate a structure for forwarding of
> adapter events and pass the address of this structure to firmware.
>
> Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
[...]
>
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index 156d1c25a3c1..9db6f8080f71 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -47,6 +47,7 @@
> #include <asm/fpu/api.h>
> #include "kvm-s390.h"
> #include "gaccess.h"
> +#include "pci.h"
>
> #define CREATE_TRACE_POINTS
> #include "trace.h"
> @@ -502,6 +503,14 @@ int kvm_arch_init(void *opaque)
> goto out;
> }
>
> + if (kvm_s390_pci_interp_allowed()) {
> + rc = kvm_s390_pci_init();
> + if (rc) {
> + pr_err("Unable to allocate AIFT for PCI\n");
> + goto out;
> + }
> + }
> +
> rc = kvm_s390_gib_init(GAL_ISC);
> if (rc)
> goto out;

We would not free the aift that was allocated by kvm_s390_pci_init
in kvm_arch_exit.
Wouldnt we re-allocate a new aift when we unload/reload kvm forgetting about the old one?

> diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c
[...]
> +static int zpci_setup_aipb(u8 nisc)
[...]
> + size = get_order(PAGE_ALIGN(ZPCI_NR_DEVICES *
> + sizeof(struct zpci_gaite)));
[...]
> + if (zpci_set_irq_ctrl(SIC_SET_AENI_CONTROLS, 0, zpci_aipb)) {
> + rc = -EIO;
> + goto free_gait;
> + }
> +
> + return 0;
> +
> +free_gait:
> + size = get_order(PAGE_ALIGN(ZPCI_NR_DEVICES *
> + sizeof(struct zpci_gaite)));

size should still be valid here?

> + free_pages((unsigned long)aift->gait, size);
> +free_sbv:
> + airq_iv_release(aift->sbv);
> + zpci_aif_sbv = 0;
> +free_aipb:
> + kfree(zpci_aipb);
> + zpci_aipb = 0;
> +
> + return rc;
> +}
> +

The remaining parts look sane.