From b84106b4e2290c081cdab521fa832596cdfea246 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Thu, 25 Feb 2016 14:35:57 -0600 Subject: PCI: Disable IO/MEM decoding for devices with non-compliant BARs The PCI config header (first 64 bytes of each device's config space) is defined by the PCI spec so generic software can identify the device and manage its usage of I/O, memory, and IRQ resources. Some non-spec-compliant devices put registers other than BARs where the BARs should be. When the PCI core sizes these "BARs", the reads and writes it does may have unwanted side effects, and the "BAR" may appear to describe non-sensical address space. Add a flag bit to mark non-compliant devices so we don't touch their BARs. Turn off IO/MEM decoding to prevent the devices from consuming address space, since we can't read the BARs to find out what that address space would be. Signed-off-by: Bjorn Helgaas Tested-by: Andi Kleen CC: stable@vger.kernel.org --- include/linux/pci.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/pci.h b/include/linux/pci.h index 27df4a6585da..5f80661d3519 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -359,6 +359,7 @@ struct pci_dev { unsigned int io_window_1k:1; /* Intel P2P bridge 1K I/O windows */ unsigned int irq_managed:1; unsigned int has_secondary_link:1; + unsigned int non_compliant_bars:1; /* broken BARs; ignore them */ pci_dev_flags_t dev_flags; atomic_t enable_cnt; /* pci_enable_device has been called */ -- cgit v1.2.3 From 0c0e0736acad4e76e718456c75d78ad95eea0011 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Tue, 1 Mar 2016 11:38:46 -0600 Subject: PCI: Set ROM shadow location in arch code, not in PCI core IORESOURCE_ROM_SHADOW means there is a copy of a device's option ROM in RAM. The existence of such a copy and its location are arch-specific. Previously the IORESOURCE_ROM_SHADOW flag was set in arch code, but the 0xC0000-0xDFFFF location was hard-coded into the PCI core. If we're using a shadow copy in RAM, disable the ROM BAR and release the address space it was consuming. Move the location information from the PCI core to the arch code that sets IORESOURCE_ROM_SHADOW. Save the location of the RAM copy in the struct resource for PCI_ROM_RESOURCE. After this change, pci_map_rom() will call pci_assign_resource() and pci_enable_rom() for these IORESOURCE_ROM_SHADOW resources, which we did not do before. This is safe because: - pci_assign_resource() will do nothing because the resource is marked IORESOURCE_PCI_FIXED, which means we can't move it, and - pci_enable_rom() will not turn on the ROM BAR's enable bit because the resource is marked IORESOURCE_ROM_SHADOW, which means it is in RAM rather than in PCI memory space. Storing the location in the struct resource means "lspci" will show the shadow location, not the value from the ROM BAR. Signed-off-by: Bjorn Helgaas --- include/linux/ioport.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/ioport.h b/include/linux/ioport.h index 24bea087e7af..2cf16673f17a 100644 --- a/include/linux/ioport.h +++ b/include/linux/ioport.h @@ -98,7 +98,7 @@ struct resource { /* PCI ROM control bits (IORESOURCE_BITS) */ #define IORESOURCE_ROM_ENABLE (1<<0) /* ROM is enabled, same as PCI_ROM_ADDRESS_ENABLE */ -#define IORESOURCE_ROM_SHADOW (1<<1) /* ROM is copy at C000:0 */ +#define IORESOURCE_ROM_SHADOW (1<<1) /* Use RAM image, not ROM BAR */ #define IORESOURCE_ROM_COPY (1<<2) /* ROM is alloc'd copy, resource field overlaid */ #define IORESOURCE_ROM_BIOS_COPY (1<<3) /* ROM is BIOS copy, resource field overlaid */ -- cgit v1.2.3 From d9c8bea179a6906a74ea42a2a162c4d1c6d9a16b Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Wed, 2 Mar 2016 21:46:50 -0600 Subject: PCI: Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY The IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY bits are unused. Remove them and code that depends on them. Signed-off-by: Bjorn Helgaas --- include/linux/ioport.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/ioport.h b/include/linux/ioport.h index 2cf16673f17a..29a6deb9f054 100644 --- a/include/linux/ioport.h +++ b/include/linux/ioport.h @@ -99,8 +99,6 @@ struct resource { /* PCI ROM control bits (IORESOURCE_BITS) */ #define IORESOURCE_ROM_ENABLE (1<<0) /* ROM is enabled, same as PCI_ROM_ADDRESS_ENABLE */ #define IORESOURCE_ROM_SHADOW (1<<1) /* Use RAM image, not ROM BAR */ -#define IORESOURCE_ROM_COPY (1<<2) /* ROM is alloc'd copy, resource field overlaid */ -#define IORESOURCE_ROM_BIOS_COPY (1<<3) /* ROM is BIOS copy, resource field overlaid */ /* PCI control bits. Shares IORESOURCE_BITS with above PCI ROM. */ #define IORESOURCE_PCI_FIXED (1<<4) /* Do not move resource */ -- cgit v1.2.3