| Message ID | 20240913112722.492144-1-boris.brezillon@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/panthor: Lock the VM resv before calling drm_gpuvm_bo_obtain_prealloc() | expand |
On Fri, Sep 13, 2024 at 01:27:22PM +0200, Boris Brezillon wrote: > drm_gpuvm_bo_obtain_prealloc() will call drm_gpuvm_bo_put() on our > pre-allocated BO if the <BO,VM> association exists. Given we > only have one ref on preallocated_vm_bo, drm_gpuvm_bo_destroy() will > be called immediately, and we have to hold the VM resv lock when > calling this function. > > Fixes: 647810ec2476 ("drm/panthor: Add the MMU/VM logical block") > Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com> Looks good to me! Reviewed-by: Liviu Dudau <liviu.dudau@arm.com> Best regards, Liviu > --- > drivers/gpu/drm/panthor/panthor_mmu.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c > index 37f1885c54c7..aa12ed2acfcf 100644 > --- a/drivers/gpu/drm/panthor/panthor_mmu.c > +++ b/drivers/gpu/drm/panthor/panthor_mmu.c > @@ -1251,9 +1251,17 @@ static int panthor_vm_prepare_map_op_ctx(struct panthor_vm_op_ctx *op_ctx, > goto err_cleanup; > } > > + /* drm_gpuvm_bo_obtain_prealloc() will call drm_gpuvm_bo_put() on our > + * pre-allocated BO if the <BO,VM> association exists. Given we > + * only have one ref on preallocated_vm_bo, drm_gpuvm_bo_destroy() will > + * be called immediately, and we have to hold the VM resv lock when > + * calling this function. > + */ > + dma_resv_lock(panthor_vm_resv(vm), NULL); > mutex_lock(&bo->gpuva_list_lock); > op_ctx->map.vm_bo = drm_gpuvm_bo_obtain_prealloc(preallocated_vm_bo); > mutex_unlock(&bo->gpuva_list_lock); > + dma_resv_unlock(panthor_vm_resv(vm)); > > /* If the a vm_bo for this <VM,BO> combination exists, it already > * retains a pin ref, and we can release the one we took earlier. > -- > 2.46.0 >
On 13/09/2024 12:27, Boris Brezillon wrote: > drm_gpuvm_bo_obtain_prealloc() will call drm_gpuvm_bo_put() on our > pre-allocated BO if the <BO,VM> association exists. Given we > only have one ref on preallocated_vm_bo, drm_gpuvm_bo_destroy() will > be called immediately, and we have to hold the VM resv lock when > calling this function. > > Fixes: 647810ec2476 ("drm/panthor: Add the MMU/VM logical block") > Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com> Reviewed-by: Steven Price <steven.price@arm.com> > --- > drivers/gpu/drm/panthor/panthor_mmu.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c > index 37f1885c54c7..aa12ed2acfcf 100644 > --- a/drivers/gpu/drm/panthor/panthor_mmu.c > +++ b/drivers/gpu/drm/panthor/panthor_mmu.c > @@ -1251,9 +1251,17 @@ static int panthor_vm_prepare_map_op_ctx(struct panthor_vm_op_ctx *op_ctx, > goto err_cleanup; > } > > + /* drm_gpuvm_bo_obtain_prealloc() will call drm_gpuvm_bo_put() on our > + * pre-allocated BO if the <BO,VM> association exists. Given we > + * only have one ref on preallocated_vm_bo, drm_gpuvm_bo_destroy() will > + * be called immediately, and we have to hold the VM resv lock when > + * calling this function. > + */ > + dma_resv_lock(panthor_vm_resv(vm), NULL); > mutex_lock(&bo->gpuva_list_lock); > op_ctx->map.vm_bo = drm_gpuvm_bo_obtain_prealloc(preallocated_vm_bo); > mutex_unlock(&bo->gpuva_list_lock); > + dma_resv_unlock(panthor_vm_resv(vm)); > > /* If the a vm_bo for this <VM,BO> combination exists, it already > * retains a pin ref, and we can release the one we took earlier.
On Fri, 13 Sep 2024 13:27:22 +0200 Boris Brezillon <boris.brezillon@collabora.com> wrote: > drm_gpuvm_bo_obtain_prealloc() will call drm_gpuvm_bo_put() on our > pre-allocated BO if the <BO,VM> association exists. Given we > only have one ref on preallocated_vm_bo, drm_gpuvm_bo_destroy() will > be called immediately, and we have to hold the VM resv lock when > calling this function. > > Fixes: 647810ec2476 ("drm/panthor: Add the MMU/VM logical block") > Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com> Queued to drm-misc-fixes. > --- > drivers/gpu/drm/panthor/panthor_mmu.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c > index 37f1885c54c7..aa12ed2acfcf 100644 > --- a/drivers/gpu/drm/panthor/panthor_mmu.c > +++ b/drivers/gpu/drm/panthor/panthor_mmu.c > @@ -1251,9 +1251,17 @@ static int panthor_vm_prepare_map_op_ctx(struct panthor_vm_op_ctx *op_ctx, > goto err_cleanup; > } > > + /* drm_gpuvm_bo_obtain_prealloc() will call drm_gpuvm_bo_put() on our > + * pre-allocated BO if the <BO,VM> association exists. Given we > + * only have one ref on preallocated_vm_bo, drm_gpuvm_bo_destroy() will > + * be called immediately, and we have to hold the VM resv lock when > + * calling this function. > + */ > + dma_resv_lock(panthor_vm_resv(vm), NULL); > mutex_lock(&bo->gpuva_list_lock); > op_ctx->map.vm_bo = drm_gpuvm_bo_obtain_prealloc(preallocated_vm_bo); > mutex_unlock(&bo->gpuva_list_lock); > + dma_resv_unlock(panthor_vm_resv(vm)); > > /* If the a vm_bo for this <VM,BO> combination exists, it already > * retains a pin ref, and we can release the one we took earlier.
diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c index 37f1885c54c7..aa12ed2acfcf 100644 --- a/drivers/gpu/drm/panthor/panthor_mmu.c +++ b/drivers/gpu/drm/panthor/panthor_mmu.c @@ -1251,9 +1251,17 @@ static int panthor_vm_prepare_map_op_ctx(struct panthor_vm_op_ctx *op_ctx, goto err_cleanup; } + /* drm_gpuvm_bo_obtain_prealloc() will call drm_gpuvm_bo_put() on our + * pre-allocated BO if the <BO,VM> association exists. Given we + * only have one ref on preallocated_vm_bo, drm_gpuvm_bo_destroy() will + * be called immediately, and we have to hold the VM resv lock when + * calling this function. + */ + dma_resv_lock(panthor_vm_resv(vm), NULL); mutex_lock(&bo->gpuva_list_lock); op_ctx->map.vm_bo = drm_gpuvm_bo_obtain_prealloc(preallocated_vm_bo); mutex_unlock(&bo->gpuva_list_lock); + dma_resv_unlock(panthor_vm_resv(vm)); /* If the a vm_bo for this <VM,BO> combination exists, it already * retains a pin ref, and we can release the one we took earlier.
drm_gpuvm_bo_obtain_prealloc() will call drm_gpuvm_bo_put() on our pre-allocated BO if the <BO,VM> association exists. Given we only have one ref on preallocated_vm_bo, drm_gpuvm_bo_destroy() will be called immediately, and we have to hold the VM resv lock when calling this function. Fixes: 647810ec2476 ("drm/panthor: Add the MMU/VM logical block") Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com> --- drivers/gpu/drm/panthor/panthor_mmu.c | 8 ++++++++ 1 file changed, 8 insertions(+)