The TBA and TMA, along with an unused IB allocation, reside at low addresses in the VM address space. A stray VM fault which hits these pages must be serviced by making their page table entries invalid. The scheduler depends upon these pages being resident and fails, preventing a debugger from inspecting the failure state.
By relocating these pages above 47 bits in the VM address space they can only be reached when bits [63:48] are set to 1. This makes it much less likely for a misbehaving program to generate accesses to them. The current placement at VA (PAGE_SIZE*2) is readily hit by a NULL access with a small offset. v2: - Move it to the reserved space to avoid concflicts with Mesa - Add macros to make reserved space management easier Cc: Arunpravin Paneer Selvam <arunpravin.paneersel...@amd.com> Cc: Christian Koenig <christian.koe...@amd.com> Signed-off-by: Jay Cornwall <jay.cornw...@amd.com> Signed-off-by: Felix Kuehling <felix.kuehl...@amd.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c | 4 +-- drivers/gpu/drm/amd/amdgpu/amdgpu_seq64.c | 7 ++--- drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h | 10 ++++++- drivers/gpu/drm/amd/amdkfd/kfd_flat_memory.c | 30 +++++++++++--------- 4 files changed, 29 insertions(+), 22 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c index 823d31f4a2a3..53d0a458d78e 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c @@ -28,9 +28,9 @@ uint64_t amdgpu_csa_vaddr(struct amdgpu_device *adev) { - uint64_t addr = adev->vm_manager.max_pfn << AMDGPU_GPU_PAGE_SHIFT; + uint64_t addr = AMDGPU_VA_RESERVED_CSA_START( + adev->vm_manager.max_pfn << AMDGPU_GPU_PAGE_SHIFT); - addr -= AMDGPU_VA_RESERVED_CSA_SIZE; addr = amdgpu_gmc_sign_extend(addr); return addr; diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_seq64.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_seq64.c index 3d0d56087d41..9e769ef50f2e 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_seq64.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_seq64.c @@ -45,11 +45,8 @@ */ static inline u64 amdgpu_seq64_get_va_base(struct amdgpu_device *adev) { - u64 addr = adev->vm_manager.max_pfn << AMDGPU_GPU_PAGE_SHIFT; - - addr -= AMDGPU_VA_RESERVED_TOP; - - return addr; + return AMDGPU_VA_RESERVED_SEQ64_START( + adev->vm_manager.max_pfn << AMDGPU_GPU_PAGE_SHIFT); } /** diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h index 2c4053b29bb3..c2407f6a7e83 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h @@ -137,9 +137,17 @@ struct amdgpu_mem_stats; /* Reserve space at top/bottom of address space for kernel use */ #define AMDGPU_VA_RESERVED_CSA_SIZE (2ULL << 20) +#define AMDGPU_VA_RESERVED_CSA_START(top) ((top) \ + - AMDGPU_VA_RESERVED_CSA_SIZE) #define AMDGPU_VA_RESERVED_SEQ64_SIZE (2ULL << 20) +#define AMDGPU_VA_RESERVED_SEQ64_START(top) (AMDGPU_VA_RESERVED_CSA_START(top) \ + - AMDGPU_VA_RESERVED_SEQ64_SIZE) +#define AMDGPU_VA_RESERVED_TRAP_SIZE (2ULL << 12) +#define AMDGPU_VA_RESERVED_TRAP_START(top) (AMDGPU_VA_RESERVED_SEQ64_START(top) \ + - AMDGPU_VA_RESERVED_TRAP_SIZE) #define AMDGPU_VA_RESERVED_BOTTOM (1ULL << 16) -#define AMDGPU_VA_RESERVED_TOP (AMDGPU_VA_RESERVED_SEQ64_SIZE + \ +#define AMDGPU_VA_RESERVED_TOP (AMDGPU_VA_RESERVED_TRAP_SIZE + \ + AMDGPU_VA_RESERVED_SEQ64_SIZE + \ AMDGPU_VA_RESERVED_CSA_SIZE) /* See vm_update_mode */ diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_flat_memory.c b/drivers/gpu/drm/amd/amdkfd/kfd_flat_memory.c index 6604a3f99c5e..f899cce25b2a 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_flat_memory.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_flat_memory.c @@ -36,6 +36,7 @@ #include <linux/mm.h> #include <linux/mman.h> #include <linux/processor.h> +#include "amdgpu_vm.h" /* * The primary memory I/O features being added for revisions of gfxip @@ -326,10 +327,16 @@ static void kfd_init_apertures_vi(struct kfd_process_device *pdd, uint8_t id) * with small reserved space for kernel. * Set them to CANONICAL addresses. */ - pdd->gpuvm_base = SVM_USER_BASE; + pdd->gpuvm_base = max(SVM_USER_BASE, AMDGPU_VA_RESERVED_BOTTOM); pdd->gpuvm_limit = pdd->dev->kfd->shared_resources.gpuvm_size - 1; + /* dGPUs: the reserved space for kernel + * before SVM + */ + pdd->qpd.cwsr_base = SVM_CWSR_BASE; + pdd->qpd.ib_base = SVM_IB_BASE; + pdd->scratch_base = MAKE_SCRATCH_APP_BASE_VI(); pdd->scratch_limit = MAKE_SCRATCH_APP_LIMIT(pdd->scratch_base); } @@ -339,18 +346,19 @@ static void kfd_init_apertures_v9(struct kfd_process_device *pdd, uint8_t id) pdd->lds_base = MAKE_LDS_APP_BASE_V9(); pdd->lds_limit = MAKE_LDS_APP_LIMIT(pdd->lds_base); - /* Raven needs SVM to support graphic handle, etc. Leave the small - * reserved space before SVM on Raven as well, even though we don't - * have to. - * Set gpuvm_base and gpuvm_limit to CANONICAL addresses so that they - * are used in Thunk to reserve SVM. - */ - pdd->gpuvm_base = SVM_USER_BASE; + pdd->gpuvm_base = AMDGPU_VA_RESERVED_BOTTOM; pdd->gpuvm_limit = pdd->dev->kfd->shared_resources.gpuvm_size - 1; pdd->scratch_base = MAKE_SCRATCH_APP_BASE_V9(); pdd->scratch_limit = MAKE_SCRATCH_APP_LIMIT(pdd->scratch_base); + + /* + * Place TBA/TMA on opposite side of VM hole to prevent + * stray faults from triggering SVM on these pages. + */ + pdd->qpd.cwsr_base = AMDGPU_VA_RESERVED_TRAP_START( + pdd->dev->adev->vm_manager.max_pfn << AMDGPU_GPU_PAGE_SHIFT); } int kfd_init_apertures(struct kfd_process *process) @@ -407,12 +415,6 @@ int kfd_init_apertures(struct kfd_process *process) return -EINVAL; } } - - /* dGPUs: the reserved space for kernel - * before SVM - */ - pdd->qpd.cwsr_base = SVM_CWSR_BASE; - pdd->qpd.ib_base = SVM_IB_BASE; } dev_dbg(kfd_device, "node id %u\n", id); -- 2.34.1