Thu, Oct 15
Wed, Oct 14
Tue, Oct 13
Thanks for fixing this. Grepping around, I believe vm_dumpset.h should also be included in:
This increases bss by ~1.5 MiB
This works for my case, but I'm not sure if this will be a problem for other platforms, or maybe for downstream codebases?
Another approach could be to just all interrupts to target the boot cpu, maybe before ap startup and maybe apply proximity restrictions after ap startup?
Mon, Oct 12
Wed, Sep 30
Sep 21 2020
Sep 10 2020
Sep 9 2020
My investigation of this problem 1 year ago lead me to think it was relocation related but I'm clueless on how that work.
I'll try to test that asap (especially arm where I don't think we had a problem).
Sep 8 2020
I've tracked this down to a particular use-after-free type bug in edk2: https://firstname.lastname@example.org/msg25730.html
Aug 31 2020
In general it seems like there's an implicit assumption that nothing will ask
for a PA that isn't in dump_avail, and if it does we just return the wrong
page since we just return some offset relative to the previous dump_avail
entry that overflows into the next entry's bitmap? It would be annoying to
fix as it means all the places that call _kvm_pa_to_bit(), and or adding some
kind of _kvm_has_pa().
Aug 27 2020
Can we reuse the algorithm from is_dumpable()? That is, if the PA corresponds
to a vm_page, use a flag to decide whether the page is to be included in the
minidump, otherwise include it so long as the PA is in dump_avail.
If dump bitmap becomes so large, may be it is better to get rid of it at all ?
You can use vm_page aflags to track dumpable state.
Aug 26 2020
Aug 25 2020
I'm curious to see the output from "sysctl vm.phys_segs" on this machine.
Aug 24 2020
Adding bitset.h to vm_page.h breaks the vhci driver. D26177 fixes that.
I augmented vm_phys_seg with a void *md_first field that is used for the pointer to the starting entry in pv_table. Is void * alright, or should I be making some new md_something type for the field?
Instead of modifying vm_phys.c to have some knowledge of superpage reservations, could we instead allocation a reservation array per vm_phys_seg, at least in the VM_PHYSSEG_SPARSE case? I think that would keep the layering clean, and make it easy to solve the issue I pointed out in vm_reserv_from_page().
Sorry, I missed the reply somehow.
Don't other PIC drivers require a similar change then? i.e., why isn't the change in pic_ipi_send() instead?
Aug 21 2020
Aug 20 2020
Jul 28 2020
I didn't knew this features, looks useful, is the variable reset by the
firmware ? (Or at least is supposed to be ?)
Jul 27 2020
Jul 26 2020
smp_rendezvous_cpus() uses a store-release to update smp_rv_waiters before
sending the IPI - why isn't that sufficient?
Jul 25 2020
Apr 3 2020
It could well be worth investigating if the changes to UEFI to properly support PcdPciDisableBusEnumeration = TRUE are less invasive than allowing runtime BAR changes
(Intel ACRN has this as TRUE)