spapr_pci: Fix config space corruption

When disabling MSI/MSIX via "ibm,change-msi" RTAS call, no check was made
if MSI or MSIX is actually supported and the MSI message was reset
unconditionally. If this happened on a device which does not support MSI
(but does support MSIX, otherwise "ibm,change-msi" would not be called),
this device would have PCIDevice::msi_cap field (MSI capability offset)
set to zero and writing a vector would actually clear PCI status.

This clears MSI message only if MSI or MSIX is present on a device.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
Alexey Kardashevskiy 2014-08-13 17:20:53 +10:00 committed by Alexander Graf
parent b981289c49
commit 3242052248

View file

@ -262,7 +262,6 @@ static void rtas_ibm_change_msi(PowerPCCPU *cpu, sPAPREnvironment *spapr,
unsigned int irq, max_irqs = 0, num = 0;
sPAPRPHBState *phb = NULL;
PCIDevice *pdev = NULL;
bool msix = false;
spapr_pci_msi *msi;
int *config_addr_key;
@ -300,7 +299,12 @@ static void rtas_ibm_change_msi(PowerPCCPU *cpu, sPAPREnvironment *spapr,
}
xics_free(spapr->icp, msi->first_irq, msi->num);
spapr_msi_setmsg(pdev, 0, msix, 0, num);
if (msi_present(pdev)) {
spapr_msi_setmsg(pdev, 0, false, 0, num);
}
if (msix_present(pdev)) {
spapr_msi_setmsg(pdev, 0, true, 0, num);
}
g_hash_table_remove(phb->msi, &config_addr);
trace_spapr_pci_msi("Released MSIs", config_addr);