[PATCH v4 3/4] arch_topology: Remove early cacheinfo error message if -ENOENT

From: Pierre Gondois
Date: Fri Apr 14 2023 - 04:15:58 EST


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@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/all/20230404-hatred-swimmer-6fecdf33b57a@spud/
Signed-off-by: Pierre Gondois <pierre.gondois@xxxxxxx>
Reviewed-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
---
drivers/base/arch_topology.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
index b1c1dd38ab01..c4b6198d7461 100644
--- a/drivers/base/arch_topology.c
+++ b/drivers/base/arch_topology.c
@@ -843,10 +843,11 @@ void __init init_cpu_topology(void)

for_each_possible_cpu(cpu) {
ret = fetch_cache_info(cpu);
- if (ret) {
+ if (!ret)
+ continue;
+ else if (ret != -ENOENT)
pr_err("Early cacheinfo failed, ret = %d\n", ret);
- break;
- }
+ return;
}
}

--
2.25.1