We observe spurious "Synchronous External Abort" exceptions
(ESR=0x96000010) and kernel crashes on Monaco-based platforms.
These faults are caused by the kernel inadvertently accessing
hypervisor-owned memory that is not properly marked as reserved.
>From boot log, The Qualcomm hypervisor reports the memory range
at 0x91a80000 of size 0x80000 (512 KiB) as hypervisor-owned:
qhee_hyp_assign_remove_memory: 0x91a80000/0x80000 -> ret 0
However, the EFI memory map provided by firmware only reserves the
subrange 0x91a40000–0x91a87fff (288 KiB). The remaining portion
(0x91a88000–0x91afffff) is incorrectly reported as conventional
memory (from efi debug):
efi: 0x000091a40000-0x000091a87fff [Reserved...]
efi: 0x000091a88000-0x0000938fffff [Conventional...]
As a result, the allocator may hand out PFNs inside the hypervisor
owned region, causing fatal aborts when the kernel accesses those
addresses.
Add a reserved-memory carveout for the Gunyah hypervisor metadata
at 0x91a80000 (512 KiB) and mark it as no-map so Linux does not
map or allocate from this area.
For the record:
Hyp version: gunyah-e78adb36e debug (2025-11-17 05:38:05 UTC)
UEFI Ver: 6.0.260122.BOOT.MXF.1.0.c1-00449-KODIAKLA-1
Fixes: 7be190e4bd ("arm64: dts: qcom: add QCS8300 platform")
Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260302142603.1113355-1-loic.poulain@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
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