Hi,
The reproducability is 100%. It's enough to only upgrade to a Fedora 30
kernel on a Fedora 29 system. The next reboot will probably be the last
reboot ever.
My Fedora bug report is here:
If it's gcc9 related, the cause may be somewhere between "Fedora's
decision to use gcc9" and "bcache needing a fix".
Rolf
On 5/6/19 7:45 PM, Rolf Fokkens wrote:
Hi,
I helped in 2013 to get bcache-tools integrated in Fedora 21
(https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx/thread/UEGAUSP377TB3KMUO7XK42KREHOUDZPG/).
Ever since it worked like a charm, and bcache laptops (we have several
at work) survived upgrading to a next Fedora release flawlessly. Since
Fedora 30 this has changed however: laptops using bcache mess up
backing store big time. It seems as if the backing device is corrupted
by random writes all over the place. It's hard to narrow down the
cause of this issue, and I'm still in the process of trial and error.
May be later on I'll have more info.
Some info:
* The laptops are using writeback caching
* The laptops have a bcache'd root file system
* It seems like the issue is in the Fedora kernel 5.0.10 for Fedora
30, but not kernel 5.0.10 for Fedora 29.
* One notable difference between the Fedora 29 and Fedora 30 kernels
is that Fedora 30 uses gcc 9 to build the kernel.
As mentioned i'm still in the process of narrowing down the cause of
the issue. But any suggestions are welcome.
Rolf
