Re: [PATCH V2] mmc: mmc_test: Pass different sg lists for non-blocking requests

From: Sai Prakash Ranjan
Date: Thu Feb 20 2020 - 03:39:57 EST


On 2020-02-19 15:14, Veerabhadrarao Badiganti wrote:
Supply a separate sg list for each of the request in non-blocking
IO test cases where two requests will be issued at same time.

Otherwise, sg memory may get unmapped when a request is done while
same memory is being accessed by controller from the other request,
and it leads to iommu errors with below call stack:

__arm_lpae_unmap+0x2e0/0x478
arm_lpae_unmap+0x54/0x70
arm_smmu_unmap+0x64/0xa4
__iommu_unmap+0xb8/0x1f0
iommu_unmap_fast+0x38/0x48
__iommu_dma_unmap+0x88/0x108
iommu_dma_unmap_sg+0x90/0xa4
sdhci_post_req+0x5c/0x78
mmc_test_start_areq+0x10c/0x120 [mmc_test]
mmc_test_area_io_seq+0x150/0x264 [mmc_test]
mmc_test_rw_multiple+0x174/0x1c0 [mmc_test]
mmc_test_rw_multiple_sg_len+0x44/0x6c [mmc_test]
mmc_test_profile_sglen_wr_nonblock_perf+0x6c/0x94 [mmc_test]
mtf_test_write+0x238/0x3cc [mmc_test]

Signed-off-by: Veerabhadrarao Badiganti <vbadigan@xxxxxxxxxxxxxx>


Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@xxxxxxxxxxxxxx>

This is reproducible on Dragonboard845c as well when performing nonblocking tests
and the patch fixes the issue.

/ # emmc_dev=mmc0:0002
/ # echo $emmc_dev > /sys/bus/mmc/drivers/mmcblk/unbind
/ # echo $emmc_dev > /sys/bus/mmc/drivers/mmc_test/bind
[ 23.715673] mmc_test mmc0:0002: Card claimed for testing.
/ # cd /sys/kernel/debug/mmc*/${emmc_dev}
/sys/kernel/debug/mmc0/mmc0:0002 # echo 42 > test
[ 32.074182] mmc0: Starting tests of card mmc0:0002...
[ 32.079484] mmc0: Test case 42. Write performance non-blocking req 1 to 512 sg elems...
[ 32.783439] mmc0: ADMA error: 0x02000000
[ 32.787411] mmc0: sdhci: ============ SDHCI REGISTER DUMP ===========
[ 32.796336] mmc0: sdhci: Sys addr: 0x00000000 | Version: 0x00006c02
[ 32.804533] mmc0: sdhci: Blk size: 0x00000200 | Blk cnt: 0x00000280
[ 32.811046] mmc0: sdhci: Argument: 0x001d0400 | Trn mode: 0x00000023
[ 32.817555] mmc0: sdhci: Present: 0x01f801f6 | Host ctl: 0x0000001f
[ 32.824062] mmc0: sdhci: Power: 0x00000001 | Blk gap: 0x00000000
[ 32.830566] mmc0: sdhci: Wake-up: 0x00000000 | Clock: 0x00000007
[ 32.837074] mmc0: sdhci: Timeout: 0x0000000e | Int stat: 0x02008000
[ 32.843582] mmc0: sdhci: Int enab: 0x03ff100b | Sig enab: 0x03ff100b
[ 32.850089] mmc0: sdhci: ACmd stat: 0x00000000 | Slot int: 0x00000000
[ 32.856596] mmc0: sdhci: Caps: 0x362dc8b2 | Caps_1: 0x0000808f
[ 32.863104] mmc0: sdhci: Cmd: 0x0000193a | Max curr: 0x00000000
[ 32.869612] mmc0: sdhci: Resp[0]: 0x00000900 | Resp[1]: 0x5b590000
[ 32.876121] mmc0: sdhci: Resp[2]: 0x1d9b7f80 | Resp[3]: 0x0a40003a
[ 32.882627] mmc0: sdhci: Host ctl2: 0x00000000
[ 32.887121] mmc0: sdhci: ADMA Err: 0x00000001 | ADMA Ptr: 0x0000000ffffff248
[ 32.894320] mmc0: sdhci: ============================================
[ 32.900831] mmc0: sdhci: ffffff200: DMA 0x0000000fffe80000, LEN 0x0000, Attr=0x21
[ 32.908391] mmc0: sdhci: ffffff20c: DMA 0x0000000fffe90000, LEN 0x0000, Attr=0x21
[ 32.915951] mmc0: sdhci: ffffff218: DMA 0x0000000fffea0000, LEN 0x0000, Attr=0x21
[ 32.923511] mmc0: sdhci: ffffff224: DMA 0x0000000fffeb0000, LEN 0x0000, Attr=0x21
[ 32.931070] mmc0: sdhci: ffffff230: DMA 0x0000000fffec0000, LEN 0x0000, Attr=0x21
[ 32.938630] mmc0: sdhci: ffffff23c: DMA 0x0000000fffed0000, LEN 0x0000, Attr=0x21
[ 32.946190] mmc0: sdhci: ffffff248: DMA 0x0000000fffee0000, LEN 0x0000, Attr=0x21
[ 32.953750] mmc0: sdhci: ffffff254: DMA 0x0000000fffef0000, LEN 0x0000, Attr=0x21
[ 32.961309] mmc0: sdhci: ffffff260: DMA 0x0000000000000000, LEN 0x0000, Attr=0x03
[ 32.968982] arm-smmu 15000000.iommu: Unhandled context fault: fsr=0x402, iova=0xfffe80480, fsynr=0x390003, cbfrsynra=0xa0, cb=1
<snip>...
[ 33.424884] [mmc_test_rw_multiple] error
[ 33.428849] mmc0: Result: ERROR (-5)
[ 33.432465] mmc0: Tests completed.
/sys/kernel/debug/mmc0/mmc0:0002 #

-Sai

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