On Wed, May 31, 2023 at 08:28:26AM -0700, Florian Fainelli wrote:

On 5/31/2023 1:53 AM, Sudeep Holla wrote:

quoted

On Tue, May 30, 2023 at 03:42:45PM -0700, Florian Fainelli wrote:

quoted

Hi Conor,

On 5/30/23 14:39, Conor Dooley wrote:

quoted

Yo Florian,

On Tue, May 30, 2023 at 01:19:55PM -0700, Florian Fainelli wrote:

quoted

From: Pierre Gondois <pierre.gondois@arm.com>

commit 3522340199cc060b70f0094e3039bdb43c3f6ee1 upstream

fetch_cache_info() tries to get the number of cache leaves/levels
for each CPU in order to pre-allocate memory for cacheinfo struct.
Allocating this memory later triggers a:
    'BUG: sleeping function called from invalid context'
in PREEMPT_RT kernels.

If there is no cache related information available in DT or ACPI,
fetch_cache_info() fails and an error message is printed:
    'Early cacheinfo failed, ret = ...'

Not having cache information should be a valid configuration.
Remove the error message if fetch_cache_info() fails with -ENOENT.

Suggested-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/all/20230404-hatred-swimmer-6fecdf33b57a@spud/ (local)
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230414081453.244787-4-pierre.gondois@arm.com (local)
Signed-off-by: Sudeep Holla <redacted>
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>

How come this now needs a backport? Did the rest of the series get
backported, but not this one since it has no fixes tag?

Humm, indeed, this has been present in v6.3.2 since I requested it to be
included. The error that I saw this morning was not -ENOENT, but -EINVAL.

With those patches applied, no more -EINVAL:

cacheinfo: Allow early level detection when DT/ACPI info is missing/broken
cacheinfo: Add arm64 early level initializer implementation
cacheinfo: Add arch specific early level initializer
cacheinfo: Add use_arch[|_cache]_info field/function

I will submit those shortly unless we think they better not be in 6.3, in
which case it would be nice to silence those -EINVAL errors.

I prefer this option instead of back porting all the above 4 as there are
some pending fixes for the issues found in those patches. I am fine if Greg
is happy with the backport, so no strong rejection from my side :).

OK, so are you suggesting that we specific check for -EINVAL and -ENOENT
rather than take all of the 4 above patches,

Yes that is my preference ATM or if possible to wait until all the fixes
are sorted for the bugs associated with above 4 commits [1] and [2].
I have queued [1] but waiting for response/patch on [2] and hence not yet
bothered Greg.

if so, any preference on how to do it given the state of 6.3 stable?

I don't understand what exactly do you mean ?

--
Regards,
Sudeep

[1] https://lore.kernel.org/all/20230508084115.1157-1-kprateek.nayak@amd.com (local)
[2] https://lore.kernel.org/all/20230518012703.GA19967@ranerica-svr.sc.intel.com (local)