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Subject: [SOLVED] dd hangs when reading large partitions
From:   Marc Gonzalez <marc.w.gonzalez@free.fr>
To:     Bart Van Assche <bvanassche@acm.org>,
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Date:   Tue, 12 Feb 2019 16:26:10 +0100
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On 11/02/2019 18:27, Marc Gonzalez wrote:

> A colleague pointed out that some memory areas are reserved downstream.
> Perhaps the FW goes haywire once the kernel touches reserved memory?

Bingo! FW quirk.

https://patchwork.kernel.org/patch/10808173/

Once the reserved memory range is extended, I am finally able
to read large partitions:

# dd if=/dev/sda of=/dev/null bs=1M
55256+0 records in
55256+0 records out
57940115456 bytes (58 GB, 54 GiB) copied, 786.165 s, 73.7 MB/s

Thanks to everyone who provided suggestions and guidance.

Regards.