Hi,

> When Linux is booted on ARM64 platform and an access to peripheral 
> returns DECERR or SLVERR on AXI.
> 
> In the above error cases how would Linux kernel handle these faults ? 
> Will it hang/recover ?

I believe that on contemporary CPUs these will result in an SError. As SErrors 
are asynchronous, and (in the absence of RAS extensions) their cause cannot be 
determined, these are treated as fatal, and the kernel will panic().

Thanks, Mark. 
In our case the peripheral returns SLVERR first time and we see the following 
print but kernel do not hang.
[  231.484186] Unhandled fault: synchronous external abort (0x92000210) at 
0x0000007f9241f880
Bus error

And from simulation we know that subsequent access to peripheral returns OKAY 
response, however we
see subsequent access fail with same above bus error when we boot Linux.

Is there a way to handle these synchronous abort  gracefully in Linux or are 
these fatal ?

Regards,
Bharat

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