From 90228ee395b71cdd64e6bc844e3d553eb9ef643f Mon Sep 17 00:00:00 2001 From: "Igor V. Kovalenko" Date: Sun, 13 Dec 2009 19:03:31 +0000 Subject: [PATCH] workaround for cmd646 bmdma register access while no dma is active This is a workaround only, and is a partial revert of a few changes to BMDMAState which removed pci_dev field on the way. - cmd646 pci_from_bm() expects bm->unit value to correspond with bm data being passed to callback as opaque pointer. This breaks when write to dma control register of second channel happens when no dma operation is in progress, so bm->unit is zero for second channel, and pci_from_bm() returns garbage pointer. Crash happens shortly after that while dereferencing that pointer. v0->v1: cleaned up dead code from pci_from_bm. Signed-off-by: Igor V. Kovalenko Signed-off-by: Blue Swirl --- hw/ide/cmd646.c | 7 ++----- hw/ide/internal.h | 1 + hw/ide/piix.c | 1 + 3 files changed, 4 insertions(+), 5 deletions(-) diff --git a/hw/ide/cmd646.c b/hw/ide/cmd646.c index e1e626e..835c98d 100644 --- a/hw/ide/cmd646.c +++ b/hw/ide/cmd646.c @@ -70,11 +70,7 @@ static void ide_map(PCIDevice *pci_dev, int region_num, static PCIIDEState *pci_from_bm(BMDMAState *bm) { - if (bm->unit == 0) { - return container_of(bm, PCIIDEState, bmdma[0]); - } else { - return container_of(bm, PCIIDEState, bmdma[1]); - } + return bm->pci_dev; } static uint32_t bmdma_readb(void *opaque, uint32_t addr) @@ -145,6 +141,7 @@ static void bmdma_map(PCIDevice *pci_dev, int region_num, BMDMAState *bm = &d->bmdma[i]; d->bus[i].bmdma = bm; bm->bus = d->bus+i; + bm->pci_dev = d; qemu_add_vm_change_state_handler(ide_dma_restart_cb, bm); register_ioport_write(addr, 1, 1, bmdma_cmd_writeb, bm); diff --git a/hw/ide/internal.h b/hw/ide/internal.h index f937daa..eb5b404 100644 --- a/hw/ide/internal.h +++ b/hw/ide/internal.h @@ -474,6 +474,7 @@ struct BMDMAState { uint8_t status; uint32_t addr; + struct PCIIDEState *pci_dev; IDEBus *bus; /* current transfer state */ uint32_t cur_addr; diff --git a/hw/ide/piix.c b/hw/ide/piix.c index de36480..2776ac3 100644 --- a/hw/ide/piix.c +++ b/hw/ide/piix.c @@ -78,6 +78,7 @@ static void bmdma_map(PCIDevice *pci_dev, int region_num, BMDMAState *bm = &d->bmdma[i]; d->bus[i].bmdma = bm; bm->bus = d->bus+i; + bm->pci_dev = d; qemu_add_vm_change_state_handler(ide_dma_restart_cb, bm); register_ioport_write(addr, 1, 1, bmdma_cmd_writeb, bm); -- 2.7.4