Re: [PATCH v2 00/32] dmaengine: at_hdmac: Fix concurrency bugs and then convert to virt-dma

From: <Tudor.Ambarus@microchip.com>
To: <vkoul@kernel.org>
Cc: <peda@axentia.se>, <du@axentia.se>, <maciej.sosnowski@intel.com>,
	<Nicolas.Ferre@microchip.com>, <mripard@kernel.org>,
	<torfl6749@gmail.com>, <linux-kernel@vger.kernel.org>,
	<dmaengine@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v2 00/32] dmaengine: at_hdmac: Fix concurrency bugs and then convert to virt-dma
Date: Fri, 4 Nov 2022 15:14:56 +0000	[thread overview]
Message-ID: <d1035d5f-02f8-a98f-fbfe-bccbdfd3920b@microchip.com> (raw)
In-Reply-To: <Y2USF24O90/dLKz7@matsya>

On 11/4/22 15:22, Vinod Koul wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> On 25-10-22, 12:02, Tudor Ambarus wrote:
>> v2:
>> - reorder patches so that fixes come first -> easier to backport to
>> stable kernels.
>> - drop the devm_request_irq() patch as we had to disable the irq anyway
>> in remove() in order to avoid spurios IRQs. Using devm variant brings no
>> palpable benefit.
>> - reword pm_ptr commit message
>>
>>
>> at_hdmac driver had poor list handling and concurrency bugs.
>> We experienced calling of the completion call twice for the
>> same descriptor. Peter Rosin encountered the same while
>> reporting a different bug:
>> https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
>>
>> Two sets of tests were performed:
>> 1/ tested just the fixes, to make sure everything is fine and the
>> concurrency bugs are squashed even without the conversion to virt-dma.
>> All went fine.
>> 2/ tested the entire series including the conversion the virt-dma
>> All went fine.
>>
>> I tested NAND (prep_dma_memcpy), MMC (prep_dma_slave_sg),
>> usart (cyclic mode), dmatest (memcpy, memset).
>> With the conversion to virt-dma I replaced the election of a new transfer
>> in the tasklet with the election of the new transfer in the interrupt
>> handler. We should have a shorter idle window as we remove the scheduling
>> latency of the tasklet. Using mtd_speedtest showed similar performances
>> when using NAND with DMA. That could be because of using a low timming
>> mode on NAND.
> 
> This does not apply on dmaengine-fixes, can you please rebase and resend
> 

Sure, I can, but on my side it applies just fine, both on the fixes and next
branches. I used git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine.git
Shall I use other tree?

Thanks,
ta

$  git am ./v2_20221025_tudor_ambarus_dmaengine_at_hdmac_fix_concurrency_bugs_and_then_convert_to_virt_dma.mbx
Applying: dmaengine: at_hdmac: Fix at_lli struct definition
Applying: dmaengine: at_hdmac: Don't start transactions at tx_submit level
Applying: dmaengine: at_hdmac: Start transfer for cyclic channels in issue_pending
Applying: dmaengine: at_hdmac: Fix premature completion of desc in issue_pending
Applying: dmaengine: at_hdmac: Do not call the complete callback on device_terminate_all
Applying: dmaengine: at_hdmac: Protect atchan->status with the channel lock
Applying: dmaengine: at_hdmac: Fix concurrency problems by removing atc_complete_all()
Applying: dmaengine: at_hdmac: Fix concurrency over descriptor
Applying: dmaengine: at_hdmac: Free the memset buf without holding the chan lock
Applying: dmaengine: at_hdmac: Fix concurrency over the active list
Applying: dmaengine: at_hdmac: Fix descriptor handling when issuing it to hardware
Applying: dmaengine: at_hdmac: Fix completion of unissued descriptor in case of errors
Applying: dmaengine: at_hdmac: Don't allow CPU to reorder channel enable
Applying: dmaengine: at_hdmac: Fix impossible condition
Applying: dmaengine: at_hdmac: Check return code of dma_async_device_register
Applying: dmaengine: at_hdmac: Do not print messages on console while holding the lock
Applying: dmaengine: at_hdmac: Return dma_cookie_status()'s ret code when txstate is NULL
Applying: dmaengine: at_hdmac: Remove superfluous cast
Applying: dmaengine: at_hdmac: Pass residue by address to avoid unnecessary implicit casts
Applying: dmaengine: at_hdmac: s/atc_get_bytes_left/atc_get_residue
Applying: dmaengine: at_hdmac: Introduce atc_get_llis_residue()
Applying: dmaengine: at_hdmac: Use devm_kzalloc() and struct_size()
Applying: dmaengine: at_hdmac: Use devm_platform_ioremap_resource
Applying: dmaengine: at_hdmac: Use devm_clk_get()
Applying: dmaengine: at_hdmac: Use pm_ptr()
Applying: dmaengine: at_hdmac: Set include entries in alphabetic order
Applying: dmaengine: at_hdmac: Keep register definitions and structures private to at_hdmac.c
Applying: dmaengine: at_hdmac: Use bitfield access macros
Applying: dmaengine: at_hdmac: Rename "dma_common" to "dma_device"
Applying: dmaengine: at_hdmac: Rename "chan_common" to "dma_chan"
Applying: dmaengine: at_hdmac: Remove unused member of at_dma_chan
Applying: dmaengine: at_hdmac: Convert driver to use virt-dma
b4 am 20221025090306.297886-1-tudor.ambarus@microchip.com
Looking up https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus%40microchip.com
Analyzing 37 messages in the thread
Checking attestation on all messages, may take a moment...
---
  [PATCH v2 1/32] dmaengine: at_hdmac: Fix at_lli struct definition
  [PATCH v2 2/32] dmaengine: at_hdmac: Don't start transactions at tx_submit level
  [PATCH v2 3/32] dmaengine: at_hdmac: Start transfer for cyclic channels in issue_pending
  [PATCH v2 4/32] dmaengine: at_hdmac: Fix premature completion of desc in issue_pending
  [PATCH v2 5/32] dmaengine: at_hdmac: Do not call the complete callback on device_terminate_all
  [PATCH v2 6/32] dmaengine: at_hdmac: Protect atchan->status with the channel lock
  [PATCH v2 7/32] dmaengine: at_hdmac: Fix concurrency problems by removing atc_complete_all()
  [PATCH v2 8/32] dmaengine: at_hdmac: Fix concurrency over descriptor
  [PATCH v2 9/32] dmaengine: at_hdmac: Free the memset buf without holding the chan lock
  [PATCH v2 10/32] dmaengine: at_hdmac: Fix concurrency over the active list
  [PATCH v2 11/32] dmaengine: at_hdmac: Fix descriptor handling when issuing it to hardware
  [PATCH v2 12/32] dmaengine: at_hdmac: Fix completion of unissued descriptor in case of errors
  [PATCH v2 13/32] dmaengine: at_hdmac: Don't allow CPU to reorder channel enable
  [PATCH v2 14/32] dmaengine: at_hdmac: Fix impossible condition
  [PATCH v2 15/32] dmaengine: at_hdmac: Check return code of dma_async_device_register
  [PATCH v2 16/32] dmaengine: at_hdmac: Do not print messages on console while holding the lock
  [PATCH v2 17/32] dmaengine: at_hdmac: Return dma_cookie_status()'s ret code when txstate is NULL
  [PATCH v2 18/32] dmaengine: at_hdmac: Remove superfluous cast
  [PATCH v2 19/32] dmaengine: at_hdmac: Pass residue by address to avoid unnecessary implicit casts
  [PATCH v2 20/32] dmaengine: at_hdmac: s/atc_get_bytes_left/atc_get_residue
  [PATCH v2 21/32] dmaengine: at_hdmac: Introduce atc_get_llis_residue()
  [PATCH v2 22/32] dmaengine: at_hdmac: Use devm_kzalloc() and struct_size()
  [PATCH v2 23/32] dmaengine: at_hdmac: Use devm_platform_ioremap_resource
  [PATCH v2 24/32] dmaengine: at_hdmac: Use devm_clk_get()
  [PATCH v2 25/32] dmaengine: at_hdmac: Use pm_ptr()
  [PATCH v2 26/32] dmaengine: at_hdmac: Set include entries in alphabetic order
  [PATCH v2 27/32] dmaengine: at_hdmac: Keep register definitions and structures private to at_hdmac.c
  [PATCH v2 28/32] dmaengine: at_hdmac: Use bitfield access macros
  [PATCH v2 29/32] dmaengine: at_hdmac: Rename "dma_common" to "dma_device"
  [PATCH v2 30/32] dmaengine: at_hdmac: Rename "chan_common" to "dma_chan"
  [PATCH v2 31/32] dmaengine: at_hdmac: Remove unused member of at_dma_chan
  [PATCH v2 32/32] dmaengine: at_hdmac: Convert driver to use virt-dma
    + Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
---
Total patches: 32
---
NOTE: Some trailers were sent to the cover letter:
      Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
NOTE: Rerun with -t to apply them to all patches
---
Cover: ./v2_20221025_tudor_ambarus_dmaengine_at_hdmac_fix_concurrency_bugs_and_then_convert_to_virt_dma.cover
 Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
 Base: not specified
       git am ./v2_20221025_tudor_ambarus_dmaengine_at_hdmac_fix_concurrency_bugs_and_then_convert_to_virt_dma.mbx

$ git log --oneline
79029dc341c7 (HEAD, vkoul-dma/fixes) dmaengine: stm32-dma: fix potential race between pause and resume