Re: Linux 5.3-rc1

Re: Linux 5.3-rc1

[James Bottomley]

[linux-scsi added to cc]
On Mon, 2019-07-22 at 15:21 -0700, Guenter Roeck wrote:
> On Sun, Jul 21, 2019 at 02:33:38PM -0700, Linus Torvalds wrote:
> 
> [ ... ]
> > 
> > Go test,
> > 
> 
> Things looked pretty good until a few days ago. Unfortunately,
> the last few days brought in a couple of issues.
> 
> riscv:virt:defconfig:scsi[virtio]
> riscv:virt:defconfig:scsi[virtio-pci]
> 
> Boot tests crash with no useful backtrace. Bisect points to
> merge ac60602a6d8f ("Merge tag 'dma-mapping-5.3-1'"). Log is at
> https://kerneltests.org/builders/qemu-riscv64-master/builds/238/steps
> /qemubuildcommand_1/logs/stdio
> 
> ppc:mpc8544ds:mpc85xx_defconfig:sata-sii3112
> ppc64:pseries:pseries_defconfig:sata-sii3112
> ppc64:pseries:pseries_defconfig:little:sata-sii3112
> ppc64:ppce500:corenet64_smp_defconfig:e5500:sata-sii3112
> 
> ata1: lost interrupt (Status 0x50)
> ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen
> ata1.00: failed command: READ DMA
> 
> and many similar errors. Boot ultimately times out. Bisect points to
> merge
> f65420df914a ("Merge tag 'scsi-fixes'").
> 
> Logs:
> https://kerneltests.org/builders/qemu-ppc64-master/builds/1212/steps/
> qemubuildcommand/logs/stdio
> https://kerneltests.org/builders/qemu-ppc-master/builds/1255/steps/qe
> mubuildcommand/logs/stdio
> 
> Guenter
> 
> ---
> riscv bisect log
> 
> # bad: [5f9e832c137075045d15cd6899ab0505cfb2ca4b] Linus 5.3-rc1
> # good: [bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1] scsi: core: take
> the DMA max mapping size into account
> git bisect start 'HEAD' 'bdd17bdef7d8'
> # good: [237f83dfbe668443b5e31c3c7576125871cca674] Merge
> git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
> git bisect good 237f83dfbe668443b5e31c3c7576125871cca674
> # good: [be8454afc50f43016ca8b6130d9673bdd0bd56ec] Merge tag 'drm-
> next-2019-07-16' of git://anongit.freedesktop.org/drm/drm
> git bisect good be8454afc50f43016ca8b6130d9673bdd0bd56ec
> # good: [d4df33b0e9925c158b313a586fb1557cf29cfdf4] Merge branch 'for-
> linus-5.2' of
> git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
> git bisect good d4df33b0e9925c158b313a586fb1557cf29cfdf4
> # good: [f90b8fda3a9d72a9422ea80ae95843697f94ea4a] ARM: dts: gemini:
> Set DIR-685 SPI CS as active low
> git bisect good f90b8fda3a9d72a9422ea80ae95843697f94ea4a
> # good: [31cc088a4f5d83481c6f5041bd6eb06115b974af] Merge tag 'drm-
> next-2019-07-19' of git://anongit.freedesktop.org/drm/drm
> git bisect good 31cc088a4f5d83481c6f5041bd6eb06115b974af
> # good: [ad21a4ce040cc41b4a085417169b558e86af56b7] dt-bindings:
> pinctrl: aspeed: Fix 'compatible' schema errors
> git bisect good ad21a4ce040cc41b4a085417169b558e86af56b7
> # good: [e6023adc5c6af79ac8ac5b17939f58091fa0d870] Merge branch
> 'core-urgent-for-linus' of
> git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
> git bisect good e6023adc5c6af79ac8ac5b17939f58091fa0d870
> # bad: [ac60602a6d8f6830dee89f4b87ee005f62eb7171] Merge tag 'dma-
> mapping-5.3-1' of git://git.infradead.org/users/hch/dma-mapping
> git bisect bad ac60602a6d8f6830dee89f4b87ee005f62eb7171
> # good: [6e67d77d673d785631b0c52314b60d3c68ebe809] perf vendor events
> s390: Add JSON files for machine type 8561
> git bisect good 6e67d77d673d785631b0c52314b60d3c68ebe809
> # good: [a0d14b8909de55139b8702fe0c7e80b69763dcfb] x86/mm, tracing:
> Fix CR2 corruption
> git bisect good a0d14b8909de55139b8702fe0c7e80b69763dcfb
> # good: [6879298bd0673840cadd1fb36d7225485504ceb4] x86/entry/64:
> Prevent clobbering of saved CR2 value
> git bisect good 6879298bd0673840cadd1fb36d7225485504ceb4
> # good: [449fa54d6815be8c2c1f68fa9dbbae9384a7c03e] dma-direct:
> correct the physical addr in dma_direct_sync_sg_for_cpu/device
> git bisect good 449fa54d6815be8c2c1f68fa9dbbae9384a7c03e
> # good: [e0c5c5e308ee9b3548844f0d88da937782b895ef] Merge tag 'perf-
> core-for-mingo-5.3-20190715' of
> git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into
> perf/urgent
> git bisect good e0c5c5e308ee9b3548844f0d88da937782b895ef
> # good: [c6dd78fcb8eefa15dd861889e0f59d301cb5230c] Merge branch 'x86-
> urgent-for-linus' of
> git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
> git bisect good c6dd78fcb8eefa15dd861889e0f59d301cb5230c
> # first bad commit: [ac60602a6d8f6830dee89f4b87ee005f62eb7171] Merge
> tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-
> mapping
> 
> ---------
> ppc/ppc64 bisect log
> 
> # bad: [5f9e832c137075045d15cd6899ab0505cfb2ca4b] Linus 5.3-rc1
> # good: [abdfd52a295fb5731ab07b5c9013e2e39f4d1cbe] Merge tag 'armsoc-
> defconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
> git bisect start 'HEAD' 'abdfd52a295f'
> # bad: [e6023adc5c6af79ac8ac5b17939f58091fa0d870] Merge branch 'core-
> urgent-for-linus' of
> git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
> git bisect bad e6023adc5c6af79ac8ac5b17939f58091fa0d870
> # bad: [f65420df914a85e33b2c8b1cab310858b2abb7c0] Merge tag 'scsi-
> fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
> git bisect bad f65420df914a85e33b2c8b1cab310858b2abb7c0
> # good: [168c79971b4a7be7011e73bf488b740a8e1135c8] Merge tag 'kbuild-
> v5.3-2' of
> git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
> git bisect good 168c79971b4a7be7011e73bf488b740a8e1135c8
> # good: [106d45f350c7cac876844dc685845cba4ffdb70b] scsi: zfcp: fix
> request object use-after-free in send path causing wrong traces
> git bisect good 106d45f350c7cac876844dc685845cba4ffdb70b
> # good: [bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1] scsi: core: take
> the DMA max mapping size into account
> git bisect good bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1
> # good: [09a4460ba4434ef0327cd26bf25f2d7afb973251] scsi: IB/iser: set
> virt_boundary_mask in the scsi host
> git bisect good 09a4460ba4434ef0327cd26bf25f2d7afb973251
> # good: [ce0ad853109733d772d26224297fda0de313bf13] scsi: mpt3sas: set
> an unlimited max_segment_size for SAS 3.0 HBAs
> git bisect good ce0ad853109733d772d26224297fda0de313bf13
> # good: [07d9aa14346489d6facae5777ceb267a1dcadbc5] scsi:
> megaraid_sas: set an unlimited max_segment_size
> git bisect good 07d9aa14346489d6facae5777ceb267a1dcadbc5
> # first bad commit: [f65420df914a85e33b2c8b1cab310858b2abb7c0] Merge
> tag 'scsi-fixes' of
> git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

When a bisect lands on a merge commit it usually indicates bad
interaction between two trees.  The way to find it is to do a bisect,
but merge up to the other side of the scsi-fixes pull before running
tests so the interaction is exposed in the bisect.

However my money is on:


commit bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1
Author: Christoph Hellwig <hch@lst.de>
Date:   Mon Jun 17 14:19:54 2019 +0200

    scsi: core: take the DMA max mapping size into account
 
Now that I look at the code again:


+       shost->max_sectors = min_t(unsigned int, shost->max_sectors,
+                       dma_max_mapping_size(dev) << SECTOR_SHIFT);

That shift looks to be the wrong way around (should be >>).  I bet
something is giving a very large number which becomes zero on left
shift, meaning max_sectors gets set to zero.

James

Re: Linux 5.3-rc1

[Guenter Roeck]

On 7/22/19 4:45 PM, James Bottomley wrote:
> [linux-scsi added to cc]
> On Mon, 2019-07-22 at 15:21 -0700, Guenter Roeck wrote:
>> On Sun, Jul 21, 2019 at 02:33:38PM -0700, Linus Torvalds wrote:
>>
>> [ ... ]
>>>
>>> Go test,
>>>
>>
>> Things looked pretty good until a few days ago. Unfortunately,
>> the last few days brought in a couple of issues.
>>
>> riscv:virt:defconfig:scsi[virtio]
>> riscv:virt:defconfig:scsi[virtio-pci]
>>
>> Boot tests crash with no useful backtrace. Bisect points to
>> merge ac60602a6d8f ("Merge tag 'dma-mapping-5.3-1'"). Log is at
>> https://kerneltests.org/builders/qemu-riscv64-master/builds/238/steps
>> /qemubuildcommand_1/logs/stdio
>>
>> ppc:mpc8544ds:mpc85xx_defconfig:sata-sii3112
>> ppc64:pseries:pseries_defconfig:sata-sii3112
>> ppc64:pseries:pseries_defconfig:little:sata-sii3112
>> ppc64:ppce500:corenet64_smp_defconfig:e5500:sata-sii3112
>>
>> ata1: lost interrupt (Status 0x50)
>> ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen
>> ata1.00: failed command: READ DMA
>>
>> and many similar errors. Boot ultimately times out. Bisect points to
>> merge
>> f65420df914a ("Merge tag 'scsi-fixes'").
>>
>> Logs:
>> https://kerneltests.org/builders/qemu-ppc64-master/builds/1212/steps/
>> qemubuildcommand/logs/stdio
>> https://kerneltests.org/builders/qemu-ppc-master/builds/1255/steps/qe
>> mubuildcommand/logs/stdio
>>
>> Guenter
>>
>> ---
>> riscv bisect log
>>
>> # bad: [5f9e832c137075045d15cd6899ab0505cfb2ca4b] Linus 5.3-rc1
>> # good: [bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1] scsi: core: take
>> the DMA max mapping size into account
>> git bisect start 'HEAD' 'bdd17bdef7d8'
>> # good: [237f83dfbe668443b5e31c3c7576125871cca674] Merge
>> git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
>> git bisect good 237f83dfbe668443b5e31c3c7576125871cca674
>> # good: [be8454afc50f43016ca8b6130d9673bdd0bd56ec] Merge tag 'drm-
>> next-2019-07-16' of git://anongit.freedesktop.org/drm/drm
>> git bisect good be8454afc50f43016ca8b6130d9673bdd0bd56ec
>> # good: [d4df33b0e9925c158b313a586fb1557cf29cfdf4] Merge branch 'for-
>> linus-5.2' of
>> git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
>> git bisect good d4df33b0e9925c158b313a586fb1557cf29cfdf4
>> # good: [f90b8fda3a9d72a9422ea80ae95843697f94ea4a] ARM: dts: gemini:
>> Set DIR-685 SPI CS as active low
>> git bisect good f90b8fda3a9d72a9422ea80ae95843697f94ea4a
>> # good: [31cc088a4f5d83481c6f5041bd6eb06115b974af] Merge tag 'drm-
>> next-2019-07-19' of git://anongit.freedesktop.org/drm/drm
>> git bisect good 31cc088a4f5d83481c6f5041bd6eb06115b974af
>> # good: [ad21a4ce040cc41b4a085417169b558e86af56b7] dt-bindings:
>> pinctrl: aspeed: Fix 'compatible' schema errors
>> git bisect good ad21a4ce040cc41b4a085417169b558e86af56b7
>> # good: [e6023adc5c6af79ac8ac5b17939f58091fa0d870] Merge branch
>> 'core-urgent-for-linus' of
>> git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
>> git bisect good e6023adc5c6af79ac8ac5b17939f58091fa0d870
>> # bad: [ac60602a6d8f6830dee89f4b87ee005f62eb7171] Merge tag 'dma-
>> mapping-5.3-1' of git://git.infradead.org/users/hch/dma-mapping
>> git bisect bad ac60602a6d8f6830dee89f4b87ee005f62eb7171
>> # good: [6e67d77d673d785631b0c52314b60d3c68ebe809] perf vendor events
>> s390: Add JSON files for machine type 8561
>> git bisect good 6e67d77d673d785631b0c52314b60d3c68ebe809
>> # good: [a0d14b8909de55139b8702fe0c7e80b69763dcfb] x86/mm, tracing:
>> Fix CR2 corruption
>> git bisect good a0d14b8909de55139b8702fe0c7e80b69763dcfb
>> # good: [6879298bd0673840cadd1fb36d7225485504ceb4] x86/entry/64:
>> Prevent clobbering of saved CR2 value
>> git bisect good 6879298bd0673840cadd1fb36d7225485504ceb4
>> # good: [449fa54d6815be8c2c1f68fa9dbbae9384a7c03e] dma-direct:
>> correct the physical addr in dma_direct_sync_sg_for_cpu/device
>> git bisect good 449fa54d6815be8c2c1f68fa9dbbae9384a7c03e
>> # good: [e0c5c5e308ee9b3548844f0d88da937782b895ef] Merge tag 'perf-
>> core-for-mingo-5.3-20190715' of
>> git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into
>> perf/urgent
>> git bisect good e0c5c5e308ee9b3548844f0d88da937782b895ef
>> # good: [c6dd78fcb8eefa15dd861889e0f59d301cb5230c] Merge branch 'x86-
>> urgent-for-linus' of
>> git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
>> git bisect good c6dd78fcb8eefa15dd861889e0f59d301cb5230c
>> # first bad commit: [ac60602a6d8f6830dee89f4b87ee005f62eb7171] Merge
>> tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-
>> mapping
>>
>> ---------
>> ppc/ppc64 bisect log
>>
>> # bad: [5f9e832c137075045d15cd6899ab0505cfb2ca4b] Linus 5.3-rc1
>> # good: [abdfd52a295fb5731ab07b5c9013e2e39f4d1cbe] Merge tag 'armsoc-
>> defconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
>> git bisect start 'HEAD' 'abdfd52a295f'
>> # bad: [e6023adc5c6af79ac8ac5b17939f58091fa0d870] Merge branch 'core-
>> urgent-for-linus' of
>> git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
>> git bisect bad e6023adc5c6af79ac8ac5b17939f58091fa0d870
>> # bad: [f65420df914a85e33b2c8b1cab310858b2abb7c0] Merge tag 'scsi-
>> fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
>> git bisect bad f65420df914a85e33b2c8b1cab310858b2abb7c0
>> # good: [168c79971b4a7be7011e73bf488b740a8e1135c8] Merge tag 'kbuild-
>> v5.3-2' of
>> git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
>> git bisect good 168c79971b4a7be7011e73bf488b740a8e1135c8
>> # good: [106d45f350c7cac876844dc685845cba4ffdb70b] scsi: zfcp: fix
>> request object use-after-free in send path causing wrong traces
>> git bisect good 106d45f350c7cac876844dc685845cba4ffdb70b
>> # good: [bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1] scsi: core: take
>> the DMA max mapping size into account
>> git bisect good bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1
>> # good: [09a4460ba4434ef0327cd26bf25f2d7afb973251] scsi: IB/iser: set
>> virt_boundary_mask in the scsi host
>> git bisect good 09a4460ba4434ef0327cd26bf25f2d7afb973251
>> # good: [ce0ad853109733d772d26224297fda0de313bf13] scsi: mpt3sas: set
>> an unlimited max_segment_size for SAS 3.0 HBAs
>> git bisect good ce0ad853109733d772d26224297fda0de313bf13
>> # good: [07d9aa14346489d6facae5777ceb267a1dcadbc5] scsi:
>> megaraid_sas: set an unlimited max_segment_size
>> git bisect good 07d9aa14346489d6facae5777ceb267a1dcadbc5
>> # first bad commit: [f65420df914a85e33b2c8b1cab310858b2abb7c0] Merge
>> tag 'scsi-fixes' of
>> git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
> 
> When a bisect lands on a merge commit it usually indicates bad
> interaction between two trees.  The way to find it is to do a bisect,
> but merge up to the other side of the scsi-fixes pull before running
> tests so the interaction is exposed in the bisect.
> 

Can you provide instructions for dummies ?

> However my money is on:
> 
> 
> commit bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1
> Author: Christoph Hellwig <hch@lst.de>
> Date:   Mon Jun 17 14:19:54 2019 +0200
> 
>      scsi: core: take the DMA max mapping size into account
>   
> Now that I look at the code again:
> 
> 
> +       shost->max_sectors = min_t(unsigned int, shost->max_sectors,
> +                       dma_max_mapping_size(dev) << SECTOR_SHIFT);
> 
> That shift looks to be the wrong way around (should be >>).  I bet
> something is giving a very large number which becomes zero on left
> shift, meaning max_sectors gets set to zero.
> 

That does indeed look bad, but changing it doesn't make a difference.

Thanks,
Guenter

Re: Linux 5.3-rc1

[James Bottomley]

On Mon, 2019-07-22 at 19:42 -0700, Guenter Roeck wrote:
> On 7/22/19 4:45 PM, James Bottomley wrote:
> > [linux-scsi added to cc]
> > On Mon, 2019-07-22 at 15:21 -0700, Guenter Roeck wrote:
> > > On Sun, Jul 21, 2019 at 02:33:38PM -0700, Linus Torvalds wrote:
> > > 
> > > [ ... ]
> > > > 
> > > > Go test,
> > > > 
> > > 
> > > Things looked pretty good until a few days ago. Unfortunately,
> > > the last few days brought in a couple of issues.
> > > 
> > > riscv:virt:defconfig:scsi[virtio]
> > > riscv:virt:defconfig:scsi[virtio-pci]
> > > 
> > > Boot tests crash with no useful backtrace. Bisect points to
> > > merge ac60602a6d8f ("Merge tag 'dma-mapping-5.3-1'"). Log is at
> > > https://kerneltests.org/builders/qemu-riscv64-master/builds/238/s
> > > teps
> > > /qemubuildcommand_1/logs/stdio
> > > 
> > > ppc:mpc8544ds:mpc85xx_defconfig:sata-sii3112
> > > ppc64:pseries:pseries_defconfig:sata-sii3112
> > > ppc64:pseries:pseries_defconfig:little:sata-sii3112
> > > ppc64:ppce500:corenet64_smp_defconfig:e5500:sata-sii3112
> > > 
> > > ata1: lost interrupt (Status 0x50)
> > > ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen
> > > ata1.00: failed command: READ DMA
> > > 
> > > and many similar errors. Boot ultimately times out. Bisect points
> > > to
> > > merge
> > > f65420df914a ("Merge tag 'scsi-fixes'").
> > > 
> > > Logs:
> > > https://kerneltests.org/builders/qemu-ppc64-master/builds/1212/st
> > > eps/
> > > qemubuildcommand/logs/stdio
> > > https://kerneltests.org/builders/qemu-ppc-master/builds/1255/step
> > > s/qe
> > > mubuildcommand/logs/stdio
> > > 
> > > Guenter
> > > 
> > > ---
> > > riscv bisect log
> > > 
> > > # bad: [5f9e832c137075045d15cd6899ab0505cfb2ca4b] Linus 5.3-rc1
> > > # good: [bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1] scsi: core:
> > > take
> > > the DMA max mapping size into account
> > > git bisect start 'HEAD' 'bdd17bdef7d8'
> > > # good: [237f83dfbe668443b5e31c3c7576125871cca674] Merge
> > > git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
> > > git bisect good 237f83dfbe668443b5e31c3c7576125871cca674
> > > # good: [be8454afc50f43016ca8b6130d9673bdd0bd56ec] Merge tag
> > > 'drm-
> > > next-2019-07-16' of git://anongit.freedesktop.org/drm/drm
> > > git bisect good be8454afc50f43016ca8b6130d9673bdd0bd56ec
> > > # good: [d4df33b0e9925c158b313a586fb1557cf29cfdf4] Merge branch
> > > 'for-
> > > linus-5.2' of
> > > git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
> > > git bisect good d4df33b0e9925c158b313a586fb1557cf29cfdf4
> > > # good: [f90b8fda3a9d72a9422ea80ae95843697f94ea4a] ARM: dts:
> > > gemini:
> > > Set DIR-685 SPI CS as active low
> > > git bisect good f90b8fda3a9d72a9422ea80ae95843697f94ea4a
> > > # good: [31cc088a4f5d83481c6f5041bd6eb06115b974af] Merge tag
> > > 'drm-
> > > next-2019-07-19' of git://anongit.freedesktop.org/drm/drm
> > > git bisect good 31cc088a4f5d83481c6f5041bd6eb06115b974af
> > > # good: [ad21a4ce040cc41b4a085417169b558e86af56b7] dt-bindings:
> > > pinctrl: aspeed: Fix 'compatible' schema errors
> > > git bisect good ad21a4ce040cc41b4a085417169b558e86af56b7
> > > # good: [e6023adc5c6af79ac8ac5b17939f58091fa0d870] Merge branch
> > > 'core-urgent-for-linus' of
> > > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
> > > git bisect good e6023adc5c6af79ac8ac5b17939f58091fa0d870
> > > # bad: [ac60602a6d8f6830dee89f4b87ee005f62eb7171] Merge tag 'dma-
> > > mapping-5.3-1' of git://git.infradead.org/users/hch/dma-mapping
> > > git bisect bad ac60602a6d8f6830dee89f4b87ee005f62eb7171
> > > # good: [6e67d77d673d785631b0c52314b60d3c68ebe809] perf vendor
> > > events
> > > s390: Add JSON files for machine type 8561
> > > git bisect good 6e67d77d673d785631b0c52314b60d3c68ebe809
> > > # good: [a0d14b8909de55139b8702fe0c7e80b69763dcfb] x86/mm,
> > > tracing:
> > > Fix CR2 corruption
> > > git bisect good a0d14b8909de55139b8702fe0c7e80b69763dcfb
> > > # good: [6879298bd0673840cadd1fb36d7225485504ceb4] x86/entry/64:
> > > Prevent clobbering of saved CR2 value
> > > git bisect good 6879298bd0673840cadd1fb36d7225485504ceb4
> > > # good: [449fa54d6815be8c2c1f68fa9dbbae9384a7c03e] dma-direct:
> > > correct the physical addr in dma_direct_sync_sg_for_cpu/device
> > > git bisect good 449fa54d6815be8c2c1f68fa9dbbae9384a7c03e
> > > # good: [e0c5c5e308ee9b3548844f0d88da937782b895ef] Merge tag
> > > 'perf-
> > > core-for-mingo-5.3-20190715' of
> > > git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into
> > > perf/urgent
> > > git bisect good e0c5c5e308ee9b3548844f0d88da937782b895ef
> > > # good: [c6dd78fcb8eefa15dd861889e0f59d301cb5230c] Merge branch
> > > 'x86-
> > > urgent-for-linus' of
> > > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
> > > git bisect good c6dd78fcb8eefa15dd861889e0f59d301cb5230c
> > > # first bad commit: [ac60602a6d8f6830dee89f4b87ee005f62eb7171]
> > > Merge
> > > tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-
> > > mapping
> > > 
> > > ---------
> > > ppc/ppc64 bisect log
> > > 
> > > # bad: [5f9e832c137075045d15cd6899ab0505cfb2ca4b] Linus 5.3-rc1
> > > # good: [abdfd52a295fb5731ab07b5c9013e2e39f4d1cbe] Merge tag
> > > 'armsoc-
> > > defconfig' of
> > > git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
> > > git bisect start 'HEAD' 'abdfd52a295f'
> > > # bad: [e6023adc5c6af79ac8ac5b17939f58091fa0d870] Merge branch
> > > 'core-
> > > urgent-for-linus' of
> > > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
> > > git bisect bad e6023adc5c6af79ac8ac5b17939f58091fa0d870
> > > # bad: [f65420df914a85e33b2c8b1cab310858b2abb7c0] Merge tag
> > > 'scsi-
> > > fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
> > > git bisect bad f65420df914a85e33b2c8b1cab310858b2abb7c0
> > > # good: [168c79971b4a7be7011e73bf488b740a8e1135c8] Merge tag
> > > 'kbuild-
> > > v5.3-2' of
> > > git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-
> > > kbuild
> > > git bisect good 168c79971b4a7be7011e73bf488b740a8e1135c8
> > > # good: [106d45f350c7cac876844dc685845cba4ffdb70b] scsi: zfcp:
> > > fix
> > > request object use-after-free in send path causing wrong traces
> > > git bisect good 106d45f350c7cac876844dc685845cba4ffdb70b
> > > # good: [bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1] scsi: core:
> > > take
> > > the DMA max mapping size into account
> > > git bisect good bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1
> > > # good: [09a4460ba4434ef0327cd26bf25f2d7afb973251] scsi: IB/iser:
> > > set
> > > virt_boundary_mask in the scsi host
> > > git bisect good 09a4460ba4434ef0327cd26bf25f2d7afb973251
> > > # good: [ce0ad853109733d772d26224297fda0de313bf13] scsi: mpt3sas:
> > > set
> > > an unlimited max_segment_size for SAS 3.0 HBAs
> > > git bisect good ce0ad853109733d772d26224297fda0de313bf13
> > > # good: [07d9aa14346489d6facae5777ceb267a1dcadbc5] scsi:
> > > megaraid_sas: set an unlimited max_segment_size
> > > git bisect good 07d9aa14346489d6facae5777ceb267a1dcadbc5
> > > # first bad commit: [f65420df914a85e33b2c8b1cab310858b2abb7c0]
> > > Merge
> > > tag 'scsi-fixes' of
> > > git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
> > 
> > When a bisect lands on a merge commit it usually indicates bad
> > interaction between two trees.  The way to find it is to do a
> > bisect,
> > but merge up to the other side of the scsi-fixes pull before
> > running
> > tests so the interaction is exposed in the bisect.
> > 
> 
> Can you provide instructions for dummies ?

do a man git-bisect and then follow the 'Automatically bisect with
temporary modifications' example.  You substitute
168c79971b4a7be7011e73bf488b740a8e1135c8 for hot-fix

> > However my money is on:
> > 
> > 
> > commit bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1
> > Author: Christoph Hellwig <hch@lst.de>
> > Date:   Mon Jun 17 14:19:54 2019 +0200
> > 
> >      scsi: core: take the DMA max mapping size into account
> >   
> > Now that I look at the code again:
> > 
> > 
> > +       shost->max_sectors = min_t(unsigned int, shost-
> > >max_sectors,
> > +                       dma_max_mapping_size(dev) << SECTOR_SHIFT);
> > 
> > That shift looks to be the wrong way around (should be >>).  I bet
> > something is giving a very large number which becomes zero on left
> > shift, meaning max_sectors gets set to zero.
> > 
> 
> That does indeed look bad, but changing it doesn't make a difference.

Odd, all the other changes are driver specific (and not in ATA) apart
from this one:

commit 7ad388d8e4c703980b7018b938cdeec58832d78d
Author: Christoph Hellwig <hch@lst.de>
Date:   Mon Jun 17 14:19:53 2019 +0200

    scsi: core: add a host / host template field for the virt boundary
 

I suppose it could be because the virt_boundary_mask isn't set, but
that should just set zero, which is what block usually does.

James

Re: Linux 5.3-rc1

[Steffen Maier]

On 7/23/19 7:28 AM, James Bottomley wrote:
> On Mon, 2019-07-22 at 19:42 -0700, Guenter Roeck wrote:
>> On 7/22/19 4:45 PM, James Bottomley wrote:
>>> [linux-scsi added to cc]
>>> On Mon, 2019-07-22 at 15:21 -0700, Guenter Roeck wrote:
>>>> On Sun, Jul 21, 2019 at 02:33:38PM -0700, Linus Torvalds wrote:
>>>>
>>>> [ ... ]
>>>>>
>>>>> Go test,
>>>>>
>>>>
>>>> Things looked pretty good until a few days ago. Unfortunately,
>>>> the last few days brought in a couple of issues.
>>>>
>>>> riscv:virt:defconfig:scsi[virtio]
>>>> riscv:virt:defconfig:scsi[virtio-pci]
>>>>
>>>> Boot tests crash with no useful backtrace. Bisect points to
>>>> merge ac60602a6d8f ("Merge tag 'dma-mapping-5.3-1'"). Log is at
>>>> https://kerneltests.org/builders/qemu-riscv64-master/builds/238/s
>>>> teps
>>>> /qemubuildcommand_1/logs/stdio
>>>>
>>>> ppc:mpc8544ds:mpc85xx_defconfig:sata-sii3112
>>>> ppc64:pseries:pseries_defconfig:sata-sii3112
>>>> ppc64:pseries:pseries_defconfig:little:sata-sii3112
>>>> ppc64:ppce500:corenet64_smp_defconfig:e5500:sata-sii3112
>>>>
>>>> ata1: lost interrupt (Status 0x50)
>>>> ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen
>>>> ata1.00: failed command: READ DMA
>>>>
>>>> and many similar errors. Boot ultimately times out. Bisect points
>>>> to
>>>> merge
>>>> f65420df914a ("Merge tag 'scsi-fixes'").
>>>>
>>>> Logs:
>>>> https://kerneltests.org/builders/qemu-ppc64-master/builds/1212/st
>>>> eps/
>>>> qemubuildcommand/logs/stdio
>>>> https://kerneltests.org/builders/qemu-ppc-master/builds/1255/step
>>>> s/qe
>>>> mubuildcommand/logs/stdio
>>>>
>>>> Guenter
>>>>
>>>> ---
>>>> riscv bisect log
>>>>
>>>> # bad: [5f9e832c137075045d15cd6899ab0505cfb2ca4b] Linus 5.3-rc1
>>>> # good: [bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1] scsi: core:
>>>> take
>>>> the DMA max mapping size into account

>>>> # first bad commit: [ac60602a6d8f6830dee89f4b87ee005f62eb7171]
>>>> Merge
>>>> tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-
>>>> mapping

>>> When a bisect lands on a merge commit it usually indicates bad
>>> interaction between two trees.  The way to find it is to do a
>>> bisect,
>>> but merge up to the other side of the scsi-fixes pull before
>>> running
>>> tests so the interaction is exposed in the bisect.
>>>
>>
>> Can you provide instructions for dummies ?
> 
> do a man git-bisect and then follow the 'Automatically bisect with
> temporary modifications' example.  You substitute
> 168c79971b4a7be7011e73bf488b740a8e1135c8 for hot-fix
> 
>>> However my money is on:
>>>
>>>
>>> commit bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1
>>> Author: Christoph Hellwig <hch@lst.de>
>>> Date:   Mon Jun 17 14:19:54 2019 +0200
>>>
>>>       scsi: core: take the DMA max mapping size into account
>>>    
>>> Now that I look at the code again:
>>>
>>>
>>> +       shost->max_sectors = min_t(unsigned int, shost-
>>>> max_sectors,
>>> +                       dma_max_mapping_size(dev) << SECTOR_SHIFT);
>>>
>>> That shift looks to be the wrong way around (should be >>).  I bet
>>> something is giving a very large number which becomes zero on left
>>> shift, meaning max_sectors gets set to zero.
>>>
>>
>> That does indeed look bad, but changing it doesn't make a difference.
> 
> Odd, all the other changes are driver specific (and not in ATA) apart
> from this one:
> 
> commit 7ad388d8e4c703980b7018b938cdeec58832d78d
> Author: Christoph Hellwig <hch@lst.de>
> Date:   Mon Jun 17 14:19:53 2019 +0200
> 
>      scsi: core: add a host / host template field for the virt boundary
> 
> 
> I suppose it could be because the virt_boundary_mask isn't set, but
> that should just set zero, which is what block usually does.

I found max_segment_size unexpectedly to be UINT_MAX with zfcp today in our CI. 
My investigations are still very early, but I thought, I share a few thoughts 
as I'm way too unfamiliar with the DMA business and thus hope for help.

Above commit introduced an unconditional call to blk_queue_virt_boundary(q, 
shost->virt_boundary_mask), _after_ blk_queue_max_segment_size(q, 
shost->max_segment_size).

Looking at the source, dma_set_max_seg_size() seems to unconditionally 
overwrite max_segment_size:

> /**
>  * blk_queue_virt_boundary - set boundary rules for bio merging
>  * @q:  the request queue for the device
>  * @mask:  the memory boundary mask
>  **/
> void blk_queue_virt_boundary(struct request_queue *q, unsigned long mask)
> {
> 	q->limits.virt_boundary_mask = mask;
> 
> 	/*
> 	 * Devices that require a virtual boundary do not support scatter/gather
> 	 * I/O natively, but instead require a descriptor list entry for each
> 	 * page (which might not be idential to the Linux PAGE_SIZE).  Because
> 	 * of that they are not limited by our notion of "segment size".
> 	 */
> 	q->limits.max_segment_size = UINT_MAX;
> }
> EXPORT_SYMBOL(blk_queue_virt_boundary);

Wild guess: Do we need to make the call to blk_queue_virt_boundary() conditional?

Cf. https://www.spinics.net/lists/linux-scsi/msg131077.html ("[PATCH v2] iser: 
explicitly set shost max_segment_size if non virtual boundary devices")

-- 
Mit freundlichen Gruessen / Kind regards
Steffen Maier

Linux on IBM Z Development

https://www.ibm.com/privacy/us/en/
IBM Deutschland Research & Development GmbH
Vorsitzender des Aufsichtsrats: Matthias Hartmann
Geschaeftsfuehrung: Dirk Wittkopp
Sitz der Gesellschaft: Boeblingen
Registergericht: Amtsgericht Stuttgart, HRB 243294

Re: Linux 5.3-rc1

[James Bottomley]

On Tue, 2019-07-23 at 07:58 -0700, Guenter Roeck wrote:
> On Tue, Jul 23, 2019 at 07:48:41AM +0200, Christoph Hellwig wrote:
> > The fix was sent last morning my time:
> > 
> > https://marc.info/?l=linux-scsi&m=156378725427719&w=2
> 
> Here is the updated bisect for the ppc scsi problem.
> 
> Guenter
> 
> ---
> # bad: [f65420df914a85e33b2c8b1cab310858b2abb7c0] Merge tag 'scsi-
> fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
> # good: [168c79971b4a7be7011e73bf488b740a8e1135c8] Merge tag 'kbuild-
> v5.3-2' of
> git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
> git bisect start 'f65420df914a' '168c79971b4a'
> # good: [106d45f350c7cac876844dc685845cba4ffdb70b] scsi: zfcp: fix
> request object use-after-free in send path causing wrong traces
> git bisect good 106d45f350c7cac876844dc685845cba4ffdb70b
> # bad: [bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1] scsi: core: take
> the DMA max mapping size into account
> git bisect bad bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1
> # good: [0cdc58580b37a160fac4b884266b8b7cb096f539] scsi: sd_zbc: Fix
> compilation warning
> git bisect good 0cdc58580b37a160fac4b884266b8b7cb096f539
> # bad: [7ad388d8e4c703980b7018b938cdeec58832d78d] scsi: core: add a
> host / host template field for the virt boundary
> git bisect bad 7ad388d8e4c703980b7018b938cdeec58832d78d
> # good: [f9b0530fa02e0c73f31a49ef743e8f44eb8e32cc] scsi: core: Fix
> race on creating sense cache
> git bisect good f9b0530fa02e0c73f31a49ef743e8f44eb8e32cc
> # first bad commit: [7ad388d8e4c703980b7018b938cdeec58832d78d] scsi:
> core: add a host / host template field for the virt boundary

And reverting that commit fixes your problem?

James

Re: Linux 5.3-rc1

[James Bottomley]

On Tue, 2019-07-23 at 16:25 +0200, Steffen Maier wrote:
> On 7/23/19 7:28 AM, James Bottomley wrote:
> > On Mon, 2019-07-22 at 19:42 -0700, Guenter Roeck wrote:
> > > On 7/22/19 4:45 PM, James Bottomley wrote:
> > > > [linux-scsi added to cc]
> > > > On Mon, 2019-07-22 at 15:21 -0700, Guenter Roeck wrote:
> > > > > On Sun, Jul 21, 2019 at 02:33:38PM -0700, Linus Torvalds
> > > > > wrote:
> > > > > 
> > > > > [ ... ]
> > > > > > 
> > > > > > Go test,
> > > > > > 
> > > > > 
> > > > > Things looked pretty good until a few days ago.
> > > > > Unfortunately,
> > > > > the last few days brought in a couple of issues.
> > > > > 
> > > > > riscv:virt:defconfig:scsi[virtio]
> > > > > riscv:virt:defconfig:scsi[virtio-pci]
> > > > > 
> > > > > Boot tests crash with no useful backtrace. Bisect points to
> > > > > merge ac60602a6d8f ("Merge tag 'dma-mapping-5.3-1'"). Log is
> > > > > at
> > > > > https://kerneltests.org/builders/qemu-riscv64-master/builds/2
> > > > > 38/s
> > > > > teps
> > > > > /qemubuildcommand_1/logs/stdio
> > > > > 
> > > > > ppc:mpc8544ds:mpc85xx_defconfig:sata-sii3112
> > > > > ppc64:pseries:pseries_defconfig:sata-sii3112
> > > > > ppc64:pseries:pseries_defconfig:little:sata-sii3112
> > > > > ppc64:ppce500:corenet64_smp_defconfig:e5500:sata-sii3112
> > > > > 
> > > > > ata1: lost interrupt (Status 0x50)
> > > > > ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6
> > > > > frozen
> > > > > ata1.00: failed command: READ DMA
> > > > > 
> > > > > and many similar errors. Boot ultimately times out. Bisect
> > > > > points
> > > > > to
> > > > > merge
> > > > > f65420df914a ("Merge tag 'scsi-fixes'").
> > > > > 
> > > > > Logs:
> > > > > https://kerneltests.org/builders/qemu-ppc64-master/builds/121
> > > > > 2/st
> > > > > eps/
> > > > > qemubuildcommand/logs/stdio
> > > > > https://kerneltests.org/builders/qemu-ppc-master/builds/1255/
> > > > > step
> > > > > s/qe
> > > > > mubuildcommand/logs/stdio
> > > > > 
> > > > > Guenter
> > > > > 
> > > > > ---
> > > > > riscv bisect log
> > > > > 
> > > > > # bad: [5f9e832c137075045d15cd6899ab0505cfb2ca4b] Linus 5.3-
> > > > > rc1
> > > > > # good: [bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1] scsi:
> > > > > core:
> > > > > take
> > > > > the DMA max mapping size into account
> > > > > # first bad commit:
> > > > > [ac60602a6d8f6830dee89f4b87ee005f62eb7171]
> > > > > Merge
> > > > > tag 'dma-mapping-5.3-1' of
> > > > > git://git.infradead.org/users/hch/dma-
> > > > > mapping
> > > > When a bisect lands on a merge commit it usually indicates bad
> > > > interaction between two trees.  The way to find it is to do a
> > > > bisect,
> > > > but merge up to the other side of the scsi-fixes pull before
> > > > running
> > > > tests so the interaction is exposed in the bisect.
> > > > 
> > > 
> > > Can you provide instructions for dummies ?
> > 
> > do a man git-bisect and then follow the 'Automatically bisect with
> > temporary modifications' example.  You substitute
> > 168c79971b4a7be7011e73bf488b740a8e1135c8 for hot-fix
> > 
> > > > However my money is on:
> > > > 
> > > > 
> > > > commit bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1
> > > > Author: Christoph Hellwig <hch@lst.de>
> > > > Date:   Mon Jun 17 14:19:54 2019 +0200
> > > > 
> > > >       scsi: core: take the DMA max mapping size into account
> > > >    
> > > > Now that I look at the code again:
> > > > 
> > > > 
> > > > +       shost->max_sectors = min_t(unsigned int, shost-
> > > > > max_sectors,
> > > > 
> > > > +                       dma_max_mapping_size(dev) <<
> > > > SECTOR_SHIFT);
> > > > 
> > > > That shift looks to be the wrong way around (should be >>).  I
> > > > bet
> > > > something is giving a very large number which becomes zero on
> > > > left
> > > > shift, meaning max_sectors gets set to zero.
> > > > 
> > > 
> > > That does indeed look bad, but changing it doesn't make a
> > > difference.
> > 
> > Odd, all the other changes are driver specific (and not in ATA)
> > apart
> > from this one:
> > 
> > commit 7ad388d8e4c703980b7018b938cdeec58832d78d
> > Author: Christoph Hellwig <hch@lst.de>
> > Date:   Mon Jun 17 14:19:53 2019 +0200
> > 
> >      scsi: core: add a host / host template field for the virt
> > boundary
> > 
> > 
> > I suppose it could be because the virt_boundary_mask isn't set, but
> > that should just set zero, which is what block usually does.
> 
> I found max_segment_size unexpectedly to be UINT_MAX with zfcp today
> in our CI. 
> My investigations are still very early, but I thought, I share a few
> thoughts 
> as I'm way too unfamiliar with the DMA business and thus hope for
> help.
> 
> Above commit introduced an unconditional call to
> blk_queue_virt_boundary(q, 
> shost->virt_boundary_mask), _after_ blk_queue_max_segment_size(q, 
> shost->max_segment_size).
> 
> Looking at the source, dma_set_max_seg_size() seems to
> unconditionally 
> overwrite max_segment_size:
> 
> > /**
> >  * blk_queue_virt_boundary - set boundary rules for bio merging
> >  * @q:  the request queue for the device
> >  * @mask:  the memory boundary mask
> >  **/
> > void blk_queue_virt_boundary(struct request_queue *q, unsigned long
> > mask)
> > {
> > 	q->limits.virt_boundary_mask = mask;
> > 
> > 	/*
> > 	 * Devices that require a virtual boundary do not support
> > scatter/gather
> > 	 * I/O natively, but instead require a descriptor list entry
> > for each
> > 	 * page (which might not be idential to the Linux
> > PAGE_SIZE).  Because
> > 	 * of that they are not limited by our notion of "segment
> > size".
> > 	 */
> > 	q->limits.max_segment_size = UINT_MAX;
> > }
> > EXPORT_SYMBOL(blk_queue_virt_boundary);
> 
> Wild guess: Do we need to make the call to blk_queue_virt_boundary()
> conditional?
> 
> Cf. https://www.spinics.net/lists/linux-scsi/msg131077.html ("[PATCH
> v2] iser: 
> explicitly set shost max_segment_size if non virtual boundary
> devices")
> 

Yes, I think so.  Can someone try this, or something like it.

Thanks,

James

---

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 9381171c2fc0..4715671a1537 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1793,7 +1793,8 @@ void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q)
 	dma_set_seg_boundary(dev, shost->dma_boundary);
 
 	blk_queue_max_segment_size(q, shost->max_segment_size);
-	blk_queue_virt_boundary(q, shost->virt_boundary_mask);
+	if (shost->virt_boundary_mask)
+		blk_queue_virt_boundary(q, shost->virt_boundary_mask);
 	dma_set_max_seg_size(dev, queue_max_segment_size(q));
 
 	/*

Re: Linux 5.3-rc1

[Guenter Roeck]

On Tue, Jul 23, 2019 at 08:14:21AM -0700, James Bottomley wrote:
> On Tue, 2019-07-23 at 07:58 -0700, Guenter Roeck wrote:
> > On Tue, Jul 23, 2019 at 07:48:41AM +0200, Christoph Hellwig wrote:
> > > The fix was sent last morning my time:
> > > 
> > > https://marc.info/?l=linux-scsi&m=156378725427719&w=2
> > 
> > Here is the updated bisect for the ppc scsi problem.
> > 
> > Guenter
> > 
> > ---
> > # bad: [f65420df914a85e33b2c8b1cab310858b2abb7c0] Merge tag 'scsi-
> > fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
> > # good: [168c79971b4a7be7011e73bf488b740a8e1135c8] Merge tag 'kbuild-
> > v5.3-2' of
> > git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
> > git bisect start 'f65420df914a' '168c79971b4a'
> > # good: [106d45f350c7cac876844dc685845cba4ffdb70b] scsi: zfcp: fix
> > request object use-after-free in send path causing wrong traces
> > git bisect good 106d45f350c7cac876844dc685845cba4ffdb70b
> > # bad: [bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1] scsi: core: take
> > the DMA max mapping size into account
> > git bisect bad bdd17bdef7d8da4d8eee254abb4c92d8a566bdc1
> > # good: [0cdc58580b37a160fac4b884266b8b7cb096f539] scsi: sd_zbc: Fix
> > compilation warning
> > git bisect good 0cdc58580b37a160fac4b884266b8b7cb096f539
> > # bad: [7ad388d8e4c703980b7018b938cdeec58832d78d] scsi: core: add a
> > host / host template field for the virt boundary
> > git bisect bad 7ad388d8e4c703980b7018b938cdeec58832d78d
> > # good: [f9b0530fa02e0c73f31a49ef743e8f44eb8e32cc] scsi: core: Fix
> > race on creating sense cache
> > git bisect good f9b0530fa02e0c73f31a49ef743e8f44eb8e32cc
> > # first bad commit: [7ad388d8e4c703980b7018b938cdeec58832d78d] scsi:
> > core: add a host / host template field for the virt boundary
> 
> And reverting that commit fixes your problem?
> 
I didn't have time to try yet; I am still on my way to work.
I'll get back later with more info. Give me a couple of hours.

Guenter

Re: Linux 5.3-rc1

[Guenter Roeck]

On Tue, Jul 23, 2019 at 08:33:15AM -0700, James Bottomley wrote:
[ ... ]
> 
> Yes, I think so.  Can someone try this, or something like it.
> 
> Thanks,
> 
> James
> 
> ---
> 
> diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
> index 9381171c2fc0..4715671a1537 100644
> --- a/drivers/scsi/scsi_lib.c
> +++ b/drivers/scsi/scsi_lib.c
> @@ -1793,7 +1793,8 @@ void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q)
>  	dma_set_seg_boundary(dev, shost->dma_boundary);
>  
>  	blk_queue_max_segment_size(q, shost->max_segment_size);
> -	blk_queue_virt_boundary(q, shost->virt_boundary_mask);
> +	if (shost->virt_boundary_mask)
> +		blk_queue_virt_boundary(q, shost->virt_boundary_mask);
>  	dma_set_max_seg_size(dev, queue_max_segment_size(q));
>  
>  	/*

This fixes the problem for me.

Guenter

Re: Linux 5.3-rc1

[James Bottomley]

On Tue, 2019-07-23 at 09:19 -0700, Guenter Roeck wrote:
> On Tue, Jul 23, 2019 at 08:33:15AM -0700, James Bottomley wrote:
> [ ... ]
> > 
> > Yes, I think so.  Can someone try this, or something like it.
> > 
> > Thanks,
> > 
> > James
> > 
> > ---
> > 
> > diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
> > index 9381171c2fc0..4715671a1537 100644
> > --- a/drivers/scsi/scsi_lib.c
> > +++ b/drivers/scsi/scsi_lib.c
> > @@ -1793,7 +1793,8 @@ void __scsi_init_queue(struct Scsi_Host
> > *shost, struct request_queue *q)
> >  	dma_set_seg_boundary(dev, shost->dma_boundary);
> >  
> >  	blk_queue_max_segment_size(q, shost->max_segment_size);
> > -	blk_queue_virt_boundary(q, shost->virt_boundary_mask);
> > +	if (shost->virt_boundary_mask)
> > +		blk_queue_virt_boundary(q, shost-
> > >virt_boundary_mask);
> >  	dma_set_max_seg_size(dev, queue_max_segment_size(q));
> >  
> >  	/*
> 
> This fixes the problem for me.

Great, thanks!

I'm thinking this is the more correct fix:

https://lore.kernel.org/linux-block/1563896932.3609.15.camel@HansenPartnership.com/

But we'll see what Jens says.

James

Re: Linux 5.3-rc1

[Steffen Maier]

On 7/23/19 6:19 PM, Guenter Roeck wrote:
> On Tue, Jul 23, 2019 at 08:33:15AM -0700, James Bottomley wrote:
> [ ... ]
>>
>> Yes, I think so.  Can someone try this, or something like it.
>>
>> Thanks,
>>
>> James
>>
>> ---
>>
>> diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
>> index 9381171c2fc0..4715671a1537 100644
>> --- a/drivers/scsi/scsi_lib.c
>> +++ b/drivers/scsi/scsi_lib.c
>> @@ -1793,7 +1793,8 @@ void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q)
>>   	dma_set_seg_boundary(dev, shost->dma_boundary);
>>   
>>   	blk_queue_max_segment_size(q, shost->max_segment_size);
>> -	blk_queue_virt_boundary(q, shost->virt_boundary_mask);
>> +	if (shost->virt_boundary_mask)
>> +		blk_queue_virt_boundary(q, shost->virt_boundary_mask);
>>   	dma_set_max_seg_size(dev, queue_max_segment_size(q));
>>   
>>   	/*
> 
> This fixes the problem for me.

+1
(on a first glimpse with zfcp)


-- 
Mit freundlichen Gruessen / Kind regards
Steffen Maier

Linux on IBM Z Development

https://www.ibm.com/privacy/us/en/
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Registergericht: Amtsgericht Stuttgart, HRB 243294

Re: Linux 5.3-rc1

[Guenter Roeck]

On Tue, Jul 23, 2019 at 09:23:34AM -0700, James Bottomley wrote:
> On Tue, 2019-07-23 at 09:19 -0700, Guenter Roeck wrote:
> > On Tue, Jul 23, 2019 at 08:33:15AM -0700, James Bottomley wrote:
> > [ ... ]
> > > 
> > > Yes, I think so.  Can someone try this, or something like it.
> > > 
> > > Thanks,
> > > 
> > > James
> > > 
> > > ---
> > > 
> > > diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
> > > index 9381171c2fc0..4715671a1537 100644
> > > --- a/drivers/scsi/scsi_lib.c
> > > +++ b/drivers/scsi/scsi_lib.c
> > > @@ -1793,7 +1793,8 @@ void __scsi_init_queue(struct Scsi_Host
> > > *shost, struct request_queue *q)
> > >  	dma_set_seg_boundary(dev, shost->dma_boundary);
> > >  
> > >  	blk_queue_max_segment_size(q, shost->max_segment_size);
> > > -	blk_queue_virt_boundary(q, shost->virt_boundary_mask);
> > > +	if (shost->virt_boundary_mask)
> > > +		blk_queue_virt_boundary(q, shost-
> > > >virt_boundary_mask);
> > >  	dma_set_max_seg_size(dev, queue_max_segment_size(q));
> > >  
> > >  	/*
> > 
> > This fixes the problem for me.
> 
> Great, thanks!
> 
> I'm thinking this is the more correct fix:
> 
> https://lore.kernel.org/linux-block/1563896932.3609.15.camel@HansenPartnership.com/
> 
> But we'll see what Jens says.

Yes, that patch also fixes the problem with sata-sii3112.

Guenter

> 
> James
>