From 375590b93b0939154513e248d46d281bf0a3f0c9 Mon Sep 17 00:00:00 2001 From: OBattler Date: Sun, 6 Apr 2025 01:05:12 +0200 Subject: [PATCH] Bochs SVGA: Add some sanity check to avoid the LFB and BIOS being mapped to either at the very bottom or top of the memory space. --- src/video/vid_bochs_vbe.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) diff --git a/src/video/vid_bochs_vbe.c b/src/video/vid_bochs_vbe.c index 84fb110c6..ac7bc00cb 100644 --- a/src/video/vid_bochs_vbe.c +++ b/src/video/vid_bochs_vbe.c @@ -686,7 +686,7 @@ bochs_vbe_pci_read(const int func, const int addr, void *priv) ret = dev->pci_rom_enable & 0x01; break; case 0x32: - ret = dev->rom_addr & 0xff; + ret = dev->rom_addr & 0xfc; break; case 0x33: ret = (dev->rom_addr & 0xff00) >> 8; @@ -743,6 +743,7 @@ bochs_vbe_pci_write(const int func, const int addr, const uint8_t val, void *pri mem_mapping_disable(&dev->linear_mapping_2); mem_mapping_disable(&dev->linear_mapping); mem_mapping_disable(&dev->svga.mapping); + mem_mapping_disable(&dev->bios_rom.mapping); if (dev->pci_conf_status & PCI_COMMAND_IO) { io_sethandler(0x03c0, 0x0020, bochs_vbe_in, NULL, NULL, bochs_vbe_out, NULL, NULL, dev); @@ -751,11 +752,13 @@ bochs_vbe_pci_write(const int func, const int addr, const uint8_t val, void *pri } if (dev->pci_conf_status & PCI_COMMAND_MEM) { mem_mapping_enable(&dev->svga.mapping); - if (dev->pci_regs[0x13] != 0x00) { + if ((dev->pci_regs[0x13] != 0x00) && (dev->pci_regs[0x13] != 0xff)) { mem_mapping_enable(&dev->linear_mapping); if (dev->pci_regs[0x13] != 0xe0) mem_mapping_enable(&dev->linear_mapping_2); } + if (dev->pci_rom_enable && (dev->rom_addr != 0x0000) && (dev->rom_addr < 0xfff8)) + mem_mapping_set_addr(&dev->bios_rom.mapping, dev->rom_addr << 16, 0x10000); } break; case 0x13: @@ -764,7 +767,7 @@ bochs_vbe_pci_write(const int func, const int addr, const uint8_t val, void *pri mem_mapping_disable(&dev->linear_mapping_2); mem_mapping_disable(&dev->linear_mapping); - if ((dev->pci_conf_status & PCI_COMMAND_MEM) && (val != 0x00)) { + if ((dev->pci_conf_status & PCI_COMMAND_MEM) && (val != 0x00) && (val != 0xff)) { mem_mapping_set_addr(&dev->linear_mapping, val << 24, 0x01000000); if (val != 0xe0) mem_mapping_set_addr(&dev->linear_mapping_2, 0xe0000000, 0x01000000); @@ -776,18 +779,26 @@ bochs_vbe_pci_write(const int func, const int addr, const uint8_t val, void *pri case 0x30: dev->pci_rom_enable = val & 0x01; mem_mapping_disable(&dev->bios_rom.mapping); - if (dev->pci_rom_enable) + if (dev->pci_rom_enable && (dev->pci_conf_status & PCI_COMMAND_MEM) && + (dev->rom_addr != 0x0000) && (dev->rom_addr < 0xfff8)) { mem_mapping_set_addr(&dev->bios_rom.mapping, dev->rom_addr << 16, 0x10000); + } break; case 0x32: dev->rom_addr = (dev->rom_addr & 0xff00) | (val & 0xfc); - if (dev->pci_rom_enable) + mem_mapping_disable(&dev->bios_rom.mapping); + if (dev->pci_rom_enable && (dev->pci_conf_status & PCI_COMMAND_MEM) && + (dev->rom_addr != 0x0000) && (dev->rom_addr < 0xfff8)) { mem_mapping_set_addr(&dev->bios_rom.mapping, dev->rom_addr << 16, 0x10000); + } break; case 0x33: dev->rom_addr = (dev->rom_addr & 0x00ff) | (val << 8); - if (dev->pci_rom_enable) + mem_mapping_disable(&dev->bios_rom.mapping); + if (dev->pci_rom_enable && (dev->pci_conf_status & PCI_COMMAND_MEM) && + (dev->rom_addr != 0x0000) && (dev->rom_addr < 0xfff8)) { mem_mapping_set_addr(&dev->bios_rom.mapping, dev->rom_addr << 16, 0x10000); + } break; } }