On 19-06-19, 12:03, Julien Thierry wrote:
I've given a run for your new version and it looks like the BP hardening is not taking place.
I believe the culprit is update_cpu_capabilities(), which in 4.4 tests for capability.desc to know where to stop (and requires all valid capabilities to have a description).
Since commit 644c2ae19 "arm64: cpufeature: Test 'matches' pointer to find the end of the list", the restriction was lifted. Unfortunately for you, the errata workarounds using BP hardening were introduced after that commit and were not given a description. So they do not get applied and also, in the current state, would prevent following entries in the errata table from getting applied.
So either 644c2ae19 needs to be backported, or the workarounds need to be given descriptions.
Okay, I have backported it and pushed it to my branch now. Thanks.