Messages in this thread | | | Date | Tue, 26 Feb 2019 11:46:53 +0100 | From | Borislav Petkov <> | Subject | Re: [PATCH] x86/boot/KASLR: skip the specified crashkernel reserved region |
| |
On Tue, Feb 26, 2019 at 11:08:42AM +0800, Pingfan Liu wrote: > I follow Baoquan's opinion. Due to the randomness caused by KASLR, a > user may be surprised to find crashkernel=x@y not working sometime.
And she/he will get told in dmesg that the allocation failed.
> If kernel can help them out of this corner automatically, then no > need to bother them with the message to use alternative method > crashkernel=M. Anyway it is a cheap method already used by other > options like hugepages and memmap in handle_mem_options(). > If commitment, then do it without failure. Or just removing > crashkernel=x@y option on x86.
I can't parse what you're trying to say here but let me repeat myself: specifying a crashkernel region should not have an influence on KASLR because this way you limit the kernel where it selects the offset. It should be other other way around: KASLR offset should be selected and *then* crashkernel region.
IOW, KASLR offset selection needs to have higher priority than crashkernel region selection.
-- Regards/Gruss, Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
| |