octeontx kernel 5.10

[Tim Harvey]

On Thu, Feb 3, 2022 at 3:54 PM Hauke Mehrtens <hauke at hauke-m.de> wrote:
>
> Hi,
>
> We would like to switch the octeontx target to kernel 5.10. Paul created
> a pull request for that:
> https://github.com/openwrt/openwrt/pull/4609
>
> Could you please test this target and report back if it works for you
> with kernel 5.10 or if we have any regressions compared to kernel 5.4.
>
> Please also report back when it is working fine for you.
>

Hauke,

Boots fine for me on a Gateworks GW6104 with a CN8031-1500MHz if I add
kpti=0 to bootargs due to CONFIG_ARM64_SW_TTBR0_PAN=y or the kernel
will crash. This must be disabled on OCTEONTX due to some processor
errata that Cavium/Marvell never cared to look into. I believe this
may have been an issue prior to bumping to 5.10 as its been something
I've just always dealt with via the kpti=0 bootarg. That said perhaps
its best to apply this:

diff --git a/target/linux/octeontx/config-5.10
b/target/linux/octeontx/config-5.10
index 6c87abf5b613..4f24e49251eb 100644
--- a/target/linux/octeontx/config-5.10
+++ b/target/linux/octeontx/config-5.10
@@ -31,6 +31,7 @@ CONFIG_ARM64_PA_BITS=48
 CONFIG_ARM64_PA_BITS_48=y
 CONFIG_ARM64_PTR_AUTH=y
 CONFIG_ARM64_SVE=y
+# CONFIG_ARM64_SW_TTBR0_PAN is not set
 CONFIG_ARM64_TAGGED_ADDR_ABI=y
 CONFIG_ARM64_UAO=y
 CONFIG_ARM64_VA_BITS=48

Best Regards,

Tim