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FAILED: patch "[PATCH] spi: spi-fsl-dspi: Free DMA memory with matching function" failed to apply to 5.4-stable tree

PATCH [email protected] 1 participant 1 message Jun 26, 2020

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The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 03fe7aaf0c3d40ef7feff2bdc7180c146989586a Mon Sep 17 00:00:00 2001
From: Krzysztof Kozlowski <[email protected]>
Date: Wed, 10 Jun 2020 17:41:57 +0200
Subject: [PATCH] spi: spi-fsl-dspi: Free DMA memory with matching function

Driver allocates DMA memory with dma_alloc_coherent() but frees it with dma_unmap_single().

This causes DMA warning during system shutdown (with DMA debugging) on Toradex Colibri VF50 module:

    WARNING: CPU: 0 PID: 1 at ../kernel/dma/debug.c:1036 check_unmap+0x3fc/0xb04
    DMA-API: fsl-edma 40098000.dma-controller: device driver frees DMA memory with wrong function
      [device address=0x0000000087040000] [size=8 bytes] [mapped as coherent] [unmapped as single]
    Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree)
      (unwind_backtrace) from [<8010bb34>] (show_stack+0x10/0x14)
      (show_stack) from [<8011ced8>] (__warn+0xf0/0x108)
      (__warn) from [<8011cf64>] (warn_slowpath_fmt+0x74/0xb8)
      (warn_slowpath_fmt) from [<8017d170>] (check_unmap+0x3fc/0xb04)
      (check_unmap) from [<8017d900>] (debug_dma_unmap_page+0x88/0x90)
      (debug_dma_unmap_page) from [<80601d68>] (dspi_release_dma+0x88/0x110)
      (dspi_release_dma) from [<80601e4c>] (dspi_shutdown+0x5c/0x80)
      (dspi_shutdown) from [<805845f8>] (device_shutdown+0x17c/0x220)
      (device_shutdown) from [<80143ef8>] (kernel_restart+0xc/0x50)
      (kernel_restart) from [<801441cc>] (__do_sys_reboot+0x18c/0x210)
      (__do_sys_reboot) from [<80100060>] (ret_fast_syscall+0x0/0x28)
    DMA-API: Mapped at:
     dma_alloc_attrs+0xa4/0x130
     dspi_probe+0x568/0x7b4
     platform_drv_probe+0x6c/0xa4
     really_probe+0x208/0x348
     driver_probe_device+0x5c/0xb4
drivers/spi/spi-fsl-dspi.c +4 -4
index a35faced0456..58190c94561f 100644
@@ -588,14 +588,14 @@ static void dspi_release_dma(struct fsl_dspi *dspi)
 		return;
 
 	if (dma->chan_tx) {
-		dma_unmap_single(dma->chan_tx->device->dev, dma->tx_dma_phys,
-				 dma_bufsize, DMA_TO_DEVICE);
+		dma_free_coherent(dma->chan_tx->device->dev, dma_bufsize,
+				  dma->tx_dma_buf, dma->tx_dma_phys);
 		dma_release_channel(dma->chan_tx);
 	}
 
 	if (dma->chan_rx) {
-		dma_unmap_single(dma->chan_rx->device->dev, dma->rx_dma_phys,
-				 dma_bufsize, DMA_FROM_DEVICE);
+		dma_free_coherent(dma->chan_rx->device->dev, dma_bufsize,
+				  dma->rx_dma_buf, dma->rx_dma_phys);
 		dma_release_channel(dma->chan_rx);
 	}
 }