Author: jhb Date: Wed Jun 5 19:29:02 2019 New Revision: 348694 URL: https://svnweb.freebsd.org/changeset/base/348694
Log: Don't simulate PBA access if the PBA is in a separate BAR. bhyve has to virtualize the MSI-X table to trap reads and writes to that table and map those to virtual interrupts that it maps real host interrupts on to. For the pending-bit-array (PBA), bhyve passes accesses from the guest directly to the hardware. bhyve's virtualization of the MSI-X table is done by intercepting all reads and writes to the BAR holding the MSI-X table. However, if the PBA is stored in the same BAR as the MSI-X table, accesses to the PBA portion of this BAR have to be forwarded to the real BAR. However, in the case that the PBA was stored in a separate BAR and it's offset in that separate BAR overlapped with the portion of the MSI-X table BAR that the table used, the handlers for the table BAR would incorrectly think that some accesses were PBA reads and writes. This caused a crash in bhyve when it indirected a NULL pointer. Fix this case by never trying to handle PBA access if the PBA lives in a separate BAR. Reported by: gallatin Tested by: gallatin Reviewed by: markj, Patrick Mooney MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D20523 Modified: head/usr.sbin/bhyve/pci_passthru.c Modified: head/usr.sbin/bhyve/pci_passthru.c ============================================================================== --- head/usr.sbin/bhyve/pci_passthru.c Wed Jun 5 16:01:05 2019 (r348693) +++ head/usr.sbin/bhyve/pci_passthru.c Wed Jun 5 19:29:02 2019 (r348694) @@ -295,7 +295,7 @@ msix_table_read(struct passthru_softc *sc, uint64_t of int index; pi = sc->psc_pi; - if (offset >= pi->pi_msix.pba_offset && + if (pi->pi_msix.pba_page != NULL && offset >= pi->pi_msix.pba_offset && offset < pi->pi_msix.pba_offset + pi->pi_msix.pba_size) { switch(size) { case 1: @@ -374,7 +374,7 @@ msix_table_write(struct vmctx *ctx, int vcpu, struct p int index; pi = sc->psc_pi; - if (offset >= pi->pi_msix.pba_offset && + if (pi->pi_msix.pba_page != NULL && offset >= pi->pi_msix.pba_offset && offset < pi->pi_msix.pba_offset + pi->pi_msix.pba_size) { switch(size) { case 1: _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
