Re: [PATCH RFC] x86: check for and defend against BIOS memory corruption

["Rafał Miłecki" <zajec5@gmail.com>]

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2008/8/28 Jeremy Fitzhardinge <jeremy@goop.org>:> Some BIOSes have been observed to corrupt memory in the low 64k.  This> patch does two things:>  - Reserves all memory which does not have to be in that area, to>   prevent it from being used as general memory by the kernel.  Things>   like the SMP trampoline are still in the memory, however.>  - Clears the reserved memory so we can observe changes to it.>  - Adds a function check_for_bios_corruption() which checks and reports on>   memory becoming unexpectedly non-zero.  Currently it's called in the>   x86 fault handler, and the powermanagement debug output.>> RFC: What other places should we check for corruption in?>> [ Alan, Rafał: could you check you see:>   1: corruption messages>   2: no crashes>  Thanks -J> ]
I was trying my best to crash system with this patch applied and failed :)
Works great.
Just wonder if I should expect any printk fromcheck_for_bios_corruption? I do not see any:
zajec@sony:~> dmesg | grep -i corrscanning 2 areas for BIOS corruption
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