From f036c7fa0ab60b7ea47560c32c78e435eb1cd214 Mon Sep 17 00:00:00 2001 From: Yian Chen Date: Thu, 17 Oct 2019 04:39:19 -0700 Subject: [PATCH] iommu/vt-d: Check VT-d RMRR region in BIOS is reported as reserved VT-d RMRR (Reserved Memory Region Reporting) regions are reserved for device use only and should not be part of allocable memory pool of OS. BIOS e820_table reports complete memory map to OS, including OS usable memory ranges and BIOS reserved memory ranges etc. x86 BIOS may not be trusted to include RMRR regions as reserved type of memory in its e820 memory map, hence validate every RMRR entry with the e820 memory map to make sure the RMRR regions will not be used by OS for any other purposes. ia64 EFI is working fine so implement RMRR validation as a dummy function Reviewed-by: Lu Baolu Reviewed-by: Sohil Mehta Signed-off-by: Yian Chen Signed-off-by: Joerg Roedel --- arch/ia64/include/asm/iommu.h | 5 +++++ arch/x86/include/asm/iommu.h | 18 ++++++++++++++++++ drivers/iommu/intel-iommu.c | 8 +++++++- 3 files changed, 30 insertions(+), 1 deletion(-) diff --git a/arch/ia64/include/asm/iommu.h b/arch/ia64/include/asm/iommu.h index 7904f591a79b..eb0db20c9d4c 100644 --- a/arch/ia64/include/asm/iommu.h +++ b/arch/ia64/include/asm/iommu.h @@ -2,6 +2,8 @@ #ifndef _ASM_IA64_IOMMU_H #define _ASM_IA64_IOMMU_H 1 +#include + /* 10 seconds */ #define DMAR_OPERATION_TIMEOUT (((cycles_t) local_cpu_data->itc_freq)*10) @@ -9,6 +11,9 @@ extern void no_iommu_init(void); #ifdef CONFIG_INTEL_IOMMU extern int force_iommu, no_iommu; extern int iommu_detected; + +static inline int __init +arch_rmrr_sanity_check(struct acpi_dmar_reserved_memory *rmrr) { return 0; } #else #define no_iommu (1) #define iommu_detected (0) diff --git a/arch/x86/include/asm/iommu.h b/arch/x86/include/asm/iommu.h index b91623d521d9..bf1ed2ddc74b 100644 --- a/arch/x86/include/asm/iommu.h +++ b/arch/x86/include/asm/iommu.h @@ -2,10 +2,28 @@ #ifndef _ASM_X86_IOMMU_H #define _ASM_X86_IOMMU_H +#include + +#include + extern int force_iommu, no_iommu; extern int iommu_detected; /* 10 seconds */ #define DMAR_OPERATION_TIMEOUT ((cycles_t) tsc_khz*10*1000) +static inline int __init +arch_rmrr_sanity_check(struct acpi_dmar_reserved_memory *rmrr) +{ + u64 start = rmrr->base_address; + u64 end = rmrr->end_address + 1; + + if (e820__mapped_all(start, end, E820_TYPE_RESERVED)) + return 0; + + pr_err(FW_BUG "No firmware reserved region can cover this RMRR [%#018Lx-%#018Lx], contact BIOS vendor for fixes\n", + start, end - 1); + return -EINVAL; +} + #endif /* _ASM_X86_IOMMU_H */ diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index e70cc1c5055f..f168cd8ee570 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -4311,13 +4311,19 @@ int __init dmar_parse_one_rmrr(struct acpi_dmar_header *header, void *arg) { struct acpi_dmar_reserved_memory *rmrr; struct dmar_rmrr_unit *rmrru; + int ret; + + rmrr = (struct acpi_dmar_reserved_memory *)header; + ret = arch_rmrr_sanity_check(rmrr); + if (ret) + return ret; rmrru = kzalloc(sizeof(*rmrru), GFP_KERNEL); if (!rmrru) goto out; rmrru->hdr = header; - rmrr = (struct acpi_dmar_reserved_memory *)header; + rmrru->base_address = rmrr->base_address; rmrru->end_address = rmrr->end_address;