On Mon, 30 Oct 2023 at 09:07, Naresh Kamboju naresh.kamboju@linaro.org wrote:
On Sat, 28 Oct 2023 at 13:12, Ard Biesheuvel ardb@kernel.org wrote:
On Fri, 27 Oct 2023 at 12:57, Naresh Kamboju naresh.kamboju@linaro.org wrote:
On Thu, 26 Oct 2023 at 21:09, Ard Biesheuvel ardb@kernel.org wrote:
On Thu, 26 Oct 2023 at 17:30, Mark Rutland mark.rutland@arm.com wrote:
On Thu, Oct 26, 2023 at 08:11:26PM +0530, Naresh Kamboju wrote:
Following kernel crash noticed on qemu-arm64 while running LTP syscalls set_robust_list test case running Linux next 6.6.0-rc7-next-20231026 ...
It looks like this is fallout from the LPA2 enablement.
According to the latest ARM ARM (ARM DDI 0487J.a), page D19-6475, that "unknown 43" (0x2b / 0b101011) is the DFSC for a level -1 translation fault:
0b101011 When FEAT_LPA2 is implemented: Translation fault, level -1.It's triggered here by an LDTR in a get_user() on a bogus userspace address. The exception is expected, and it's supposed to be handled via the exception fixups, but the LPA2 patches didn't update the fault_info table entries for all the level -1 faults, and so those all get handled by do_bad() and don't call fixup_exception(), causing them to be fatal.
It should be relatively simple to update the fault_info table for the level -1 faults, but given the other issues we're seeing I think it's probably worth dropping the LPA2 patches for the moment.
Thanks for the analysis Mark.
I agree that this should not be difficult to fix, but given the other CI problems and identified loose ends, I am not going to object to dropping this partially or entirely at this point. I'm sure everybody will be thrilled to go over those 60 patches again after I rebase them onto v6.7-rc1 :-)
I am happy to test any proposed fix patch.
Thanks Naresh. Patch attached.
This patch did not solve the reported problem. Test log links,
Oops, sorry about that.
Fixed patch attched.