From: Christoph Hellwig hch@lst.de
[ Upstream commit a899d542b687c9b04ccbd9eefabc829ba5fef791 ]
This reverts commit fc156629b23a21181e473e60341e3a78af25a1d4.
This commit manages to do three API violations at once:
- dereference the return value of dma_alloc_attrs with the DMA_ATTR_NO_KERNEL_MAPPING mapping, which is clearly forbidden and will do the wrong thing on various dma mapping implementations. The fact that dma-direct uses a struct page as a cookie is an undocumented implementation detail - include dma-map-ops.h and use pgprot_dmacoherent despite a clear comment documenting that this is not acceptable - use of the VM_DMA_COHERENT for something that is not the dma-mapping code - use of VM_FLUSH_RESET_PERMS for vmap, while it is only supported for vmalloc
Acked-by: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sibi Sankar quic_sibis@quicinc.com Signed-off-by: Bjorn Andersson andersson@kernel.org Link: https://lore.kernel.org/r/20230117085840.32356-6-quic_sibis@quicinc.com Stable-dep-of: 57f72170a2b2 ("remoteproc: qcom_q6v5_mss: Use a carveout to authenticate modem headers") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/remoteproc/qcom_q6v5_mss.c | 38 +++++------------------------- 1 file changed, 6 insertions(+), 32 deletions(-)
diff --git a/drivers/remoteproc/qcom_q6v5_mss.c b/drivers/remoteproc/qcom_q6v5_mss.c index fddb63cffee07..a8b141db4de63 100644 --- a/drivers/remoteproc/qcom_q6v5_mss.c +++ b/drivers/remoteproc/qcom_q6v5_mss.c @@ -10,7 +10,6 @@ #include <linux/clk.h> #include <linux/delay.h> #include <linux/devcoredump.h> -#include <linux/dma-map-ops.h> #include <linux/dma-mapping.h> #include <linux/interrupt.h> #include <linux/kernel.h> @@ -933,52 +932,27 @@ static void q6v5proc_halt_axi_port(struct q6v5 *qproc, static int q6v5_mpss_init_image(struct q6v5 *qproc, const struct firmware *fw, const char *fw_name) { - unsigned long dma_attrs = DMA_ATTR_FORCE_CONTIGUOUS | DMA_ATTR_NO_KERNEL_MAPPING; - unsigned long flags = VM_DMA_COHERENT | VM_FLUSH_RESET_PERMS; - struct page **pages; - struct page *page; + unsigned long dma_attrs = DMA_ATTR_FORCE_CONTIGUOUS; dma_addr_t phys; void *metadata; int mdata_perm; int xferop_ret; size_t size; - void *vaddr; - int count; + void *ptr; int ret; - int i;
metadata = qcom_mdt_read_metadata(fw, &size, fw_name, qproc->dev); if (IS_ERR(metadata)) return PTR_ERR(metadata);
- page = dma_alloc_attrs(qproc->dev, size, &phys, GFP_KERNEL, dma_attrs); - if (!page) { + ptr = dma_alloc_attrs(qproc->dev, size, &phys, GFP_KERNEL, dma_attrs); + if (!ptr) { kfree(metadata); dev_err(qproc->dev, "failed to allocate mdt buffer\n"); return -ENOMEM; }
- count = PAGE_ALIGN(size) >> PAGE_SHIFT; - pages = kmalloc_array(count, sizeof(struct page *), GFP_KERNEL); - if (!pages) { - ret = -ENOMEM; - goto free_dma_attrs; - } - - for (i = 0; i < count; i++) - pages[i] = nth_page(page, i); - - vaddr = vmap(pages, count, flags, pgprot_dmacoherent(PAGE_KERNEL)); - kfree(pages); - if (!vaddr) { - dev_err(qproc->dev, "unable to map memory region: %pa+%zx\n", &phys, size); - ret = -EBUSY; - goto free_dma_attrs; - } - - memcpy(vaddr, metadata, size); - - vunmap(vaddr); + memcpy(ptr, metadata, size);
/* Hypervisor mapping to access metadata by modem */ mdata_perm = BIT(QCOM_SCM_VMID_HLOS); @@ -1008,7 +982,7 @@ static int q6v5_mpss_init_image(struct q6v5 *qproc, const struct firmware *fw, "mdt buffer not reclaimed system may become unstable\n");
free_dma_attrs: - dma_free_attrs(qproc->dev, size, page, phys, dma_attrs); + dma_free_attrs(qproc->dev, size, ptr, phys, dma_attrs); kfree(metadata);
return ret < 0 ? ret : 0;