On 8/23/26 21:14, E Shattow wrote:
> Hi Milad,  adding CC: Sughosh
> 
> On 8/23/26 06:34, Milad wrote:
>> Thanks alot for the reply. I finished the bisect between v2026.04 (good)
>> and v2026.07 (bad). Results are below.
>>
>> commit a3075db94d49f415658bf7e961e1eae90d9abc33
>> Author: Marek Vasut <[email protected]>
>> Date: Wed Jan 28 00:48:40 2026 +0100
>>
>>     lmb: Reinstate access to memory above ram_top
>>
>>     Revert commit eb052cbb896f ("lmb: add and reserve memory above ram_top")
>>     and commit 1a48b0be93d4 ("lmb: prohibit allocations above ram_top even
>> from
>>     same bank"). These are based on incorrect assumption of the first
>> commit, that
>>     "U-Boot does not use memory above ram_top". While U-Boot itself indeed
>> does
>>     not and should not use memory above ram_top, user can perfectly well use
>>     that memory from the U-Boot shell for example to load content in there.
>>
>>     Right now the attempt to use that memory to load large image using TFTP
>> ends
>>     with "TFTP error: trying to overwrite reserved memory...". With this
>> change
>>     in place, the memory can be used again.
>>
>>     Fixes: eb052cbb896f ("lmb: add and reserve memory above ram_top")
>>     Fixes: 1a48b0be93d4 ("lmb: prohibit allocations above ram_top even from
>> same bank")
>>     Reported-by: Yuya Hamamachi <[email protected]>
>>     Signed-off-by: Marek Vasut <[email protected]>
>>
>> Each commit was built and flash-tested on real hardware (VisionFive 2,
>> v1.3B, 8GiB), boot result confirmed via serial console each round. Bisect
>> log below for reference.
>>
>> Whats interesting is that the actual regressing commit isn't an
>> MMC-subsystem change at all — it's an lmb (memory reservation) change
>> reverting an earlier restriction on memory above ram_top. My guess (not
>> verified, just an observation) is that the MMC driver's DMA buffer
>> allocation may be relying on that memory being reserved or excluded and
>> removing that reservation could be causing DMA into an unsafe or improperly
>> handled memory region during SD card init which would line up with the
>> "voltage select" / "Error reading cluster" failures I've been seeing right
>> at the data transfer stage. Could well be unrelated to the actual mechanism
>> since the voltage select error also shows when boot works fine.
>>
>> Happy to test a fix or patch if one comes up.
>>
>> --- bisect log ---
>> git bisect start
>> # status: waiting for both good and bad commits
>> # bad: [ece349ade2973e220f524ce59e59711cc919263f] Prepare v2026.07
>> git bisect bad ece349ade2973e220f524ce59e59711cc919263f
>> # status: waiting for good commit(s), bad commit known
>> # good: [88dc2788777babfd6322fa655df549a019aa1e69] Prepare v2026.04
>> git bisect good 88dc2788777babfd6322fa655df549a019aa1e69
>> # bad: [f98f2e26125f111df60d1ebdab483f91cc1f8e71] ls1043a: add env
>> variables to assist boot
>> git bisect bad f98f2e26125f111df60d1ebdab483f91cc1f8e71
>> # bad: [0e16a814399510d1785cf87c4a9a1c66dd790487] Merge branch 'master' of
>> https://source.denx.de/u-boot/custodians/u-boot-sunxi into next
>> git bisect bad 0e16a814399510d1785cf87c4a9a1c66dd790487
>> # good: [fe6484b402759dba6024cf2f8c212b27f769a0d7] bootm: fix booting
>> kernel_noload image
>> git bisect good fe6484b402759dba6024cf2f8c212b27f769a0d7
>> # bad: [7f35a4251dae2b1c94c959ac15cf4d0814485a88] sandbox: symbol
>> CONFIG_DM_SOUND does not exist
>> git bisect bad 7f35a4251dae2b1c94c959ac15cf4d0814485a88
>> # good: [04e96eb693cdb26204143629c56d45a353390a75] disk: fix DOS_PARTITION
>> dependencies
>> git bisect good 04e96eb693cdb26204143629c56d45a353390a75
>> # good: [a5fcbd5a83553b3803df28422410c9fd22adaec6] net: Move network PHY
>> under NETDEVICES
>> git bisect good a5fcbd5a83553b3803df28422410c9fd22adaec6
>> # good: [6dc75d440dbdd3e2ac24ae5bb0ed51123bee8c33] Merge tag 'net-20260312'
>> of https://source.denx.de/u-boot/custodians/u-boot-net into next
>> git bisect good 6dc75d440dbdd3e2ac24ae5bb0ed51123bee8c33
>> # good: [2f52473884723751316388af30a95419905b1cd3] Merge branch 'next' of
>> https://source.denx.de/u-boot/custodians/u-boot-riscv into next
>> git bisect good 2f52473884723751316388af30a95419905b1cd3
>> # good: [c664b4d5f30a704003b97823a5ad6361cb16fbe8] spl: Make UFS available
>> for SPL builds
>> git bisect good c664b4d5f30a704003b97823a5ad6361cb16fbe8
>> # good: [dba21bf0b6ececa4bbc15ac93b3cdf4b09286ed7] Merge tag
>> 'u-boot-ufs-20260313' of https://source.denx.de/u-boot/custodians/u-boot-ufs
>> into next
>> git bisect good dba21bf0b6ececa4bbc15ac93b3cdf4b09286ed7
>> # bad: [e7ad95aa3f1180823e07dd30c8c24494a07ca814] spl: spi: fix loss of
>> spl_load() error on soft reset
>> git bisect bad e7ad95aa3f1180823e07dd30c8c24494a07ca814
>>
>> commit a3075db94d49f415658bf7e961e1eae90d9abc33 is the first bad commit
>>
>> On Fri, 21 Aug 2026, 20:49 Quentin Schulz, <[email protected]> wrote:
>>
>>> Hi Milad,
>>>
>>> On 7/29/26 12:29 PM, Milad wrote:
>>>> [You don't often get email from [email protected]. Learn why this is
>>> important at https://aka.ms/LearnAboutSenderIdentification ]
>>>>
>>>> Thanks to both for the replies.
>>>>
>>>> I built and tested both v2025.10 and v2026.01 on my board (VisionFive 2,
>>>> v1.3B, 8GiB), and can confirm both boot the SD card correctly, no cluster
>>>> read failure, straight into GRUB and Debian on both. Only v2026.07 fails
>>>> for me.
>>>>
>>>> So the regression window looks to be somewhere between v2026.01 and
>>>> v2026.07. Full serial logs for both below.
>>>>
>>>
>>> Could you bisect which commit broke it? That would surely help people
>>> have an idea of what could have gone wrong and get motivated to fix the
>>> issue :)
>>>
>>> Cheers,
>>> Quentin
>>>
>>
> 
> MMC driver access on JH-7110 SoC from U-Boot does not tolerate beyond
> 32-bit address. I've now completely forgotten what the test procedure
> was for this earlier but it followed with a discussion via IRC (and
> further mailing list follow-up [1]) about the change in memory model
> access within u-boot that broke uSD access beyond the addressing limit
> for JH-7110 SoC.
> 
> 1:
> https://lore.kernel.org/u-boot/[email protected]/
> 
> Search mailing list archives for my name and Sughosh together where
> you'll find the intersection of that discussion over a few threads.
> Initially we don't understand the problem and then when there are
> suggested fixes I then try to ensure enough testing has been done to
> confirm the corrections made by Sughosh. Probably we missed something? I
> was donated a Mars CM and a Star64 with eMMC module, so there is some
> testing I might be capable of doing with these hardware yet on request.
> 
> Thanks,
> 
> -E

P.S. I don't know what I am doing CC'ing outdated e-mail address for
Sughosh. CC'ing now from MAINTAINERS like I should have done a minute ago.

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