On Wed, Apr 24, 2019, 03:46 Baoquan He <bhe@xxxxxxxxxx> wrote: > > On 04/24/19 at 02:18pm, Dave Young wrote: > > On 04/24/19 at 01:41pm, Baoquan He wrote: > > > On 04/24/19 at 02:47am, Junichi Nomura wrote: > > > > On 4/24/19 2:15 AM, Kairui Song wrote: > > > > > On Mon, Apr 22, 2019 at 11:21 PM Junichi Nomura <j-nomura@xxxxxxxxxxxxx> wrote: > > > > >> Is the mapping of ACPI tables just by luck, too? > > > > > > > > > > Good question, they should have same issue with systab, I ignored this one. > > > > > Then in first kernel when doing kexec it should ensure both ACPI > > > > > tables and the EFI systab are mapped, that should cover everything and > > > > > make it work. > > > > > > > > Right. > > > > > > > > > Is there anything else missing? > > > > No, as far as I looked around get_rsdp_addr(). > > > > > > Have made a draft patch to build ident mapping for ACPI tables too, it's > > > based on Kairui's patch. Dave has tested on his t400s laptop, and > > > passed. Please check if this adding is OK. > > > > > > Kairui, you can add this into your patch to make a new one and resend. > > > Or I can combine them and send for you today. > > > > > Since I can not reproduce the acpi table accessing fault with Kairui's patch, > > the test is just sanity testing on same hardware. But the patch looks > > good. > > Yes, usually vendor will put these efi systab, ACPI tables together. See > the regions you listed on your t420 laptop in another mail: > da99f000 - dae9efff Reserved (efi systab fall in this region) > daf9f000 - daffefff ACPI tables > > We build 1:1 mapping for kexec kernel down to PMD level. Means for a > region, it will align starting address down to PMD size, and align end > address up to PMD size. So the end of efi systab, 0xdae9efff, will cause > mapping built for the 2MB area, 0xdae00000-0xdaf00000. Clearly ACPI > tables are covered by that PMD entry. That's why only efi systab > mapping is built, accessing ACPI tables doesn't cause error. > > But we can't assume they will be put together always, so need map ACPI > tables too. > > > > > With Kairui's fix+ this acpi fix and Junichi's patch everything works. > > Can anyone send them for example patch 1/2: kexec early mapping for > > efi/acpi, patch 2/2: Junichi's previous patch. > > Kairui is having a workshop in the US, I can make a patchset to > include these two patches. > > For patch 1/2, I will combine the patch Kairui posted and my draft patch, > Kairui is the author certainly, since he debugged and found out the root > cause, and posted v1 when I was on vacation last week. > > For patch 2/2, I think the version Boris organized is good. > http://lkml.kernel.org/r/20190416095209.GG27892@xxxxxxx > Thanks a lot Bao! I was offline for about 1 day due to timezone and flight, I have no problem with this and the ACPI mapping part looks good to me. _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
