| Message ID | 20231024100923.12724-1-julien@xen.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [for-4.19] docs/arm: Document where Xen should be loaded in memory | expand |
On 24/10/2023 11:09, Julien Grall wrote: > From: Julien Grall <jgrall@amazon.com> > > In commit 9d267c049d92 ("xen/arm64: Rework the memory layout"), > we decided to require Xen to be loaded below 5 TiB to simplify > the logic to enable the MMU. The limit was decided based on > how known platform boot plus some slack. > > We had a recent report that this is not sufficient on the AVA > platform with a old firmware [1]. But the restriction is not > going to change in Xen 4.18. So document the limit clearly > in docs/misc/arm/booting.txt I forgot to add a link to [1] 20231013122658.1270506-3-leo.yan@linaro.org Cheers,
Hi Julien, On 24/10/2023 12:09, Julien Grall wrote: > > > From: Julien Grall <jgrall@amazon.com> > > In commit 9d267c049d92 ("xen/arm64: Rework the memory layout"), > we decided to require Xen to be loaded below 5 TiB to simplify s/5/2 > the logic to enable the MMU. The limit was decided based on > how known platform boot plus some slack. > > We had a recent report that this is not sufficient on the AVA > platform with a old firmware [1]. But the restriction is not > going to change in Xen 4.18. So document the limit clearly > in docs/misc/arm/booting.txt > > Signed-off-by: Julien Grall <jgrall@amazon.com> > > ---- one less '-' > > I couldn't find a nice way to document it in SUPPORT.md. So I decided > to only document the restrict in docs/misc/arm/booting.txt for now. > > I also couldn't find any way from GRUB/UEFI (I didn't look much) to > specify the loading address. > --- > docs/misc/arm/booting.txt | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/docs/misc/arm/booting.txt b/docs/misc/arm/booting.txt > index 02f7bb65ec6d..c6bdeafe5e5b 100644 > --- a/docs/misc/arm/booting.txt > +++ b/docs/misc/arm/booting.txt > @@ -21,6 +21,10 @@ The exceptions to this on 32-bit ARM are as follows: > zImage protocol should still be used and not the stricter "raw > (non-zImage)" protocol described in arm/Booting. > > +The exceptions to this on 64-bit ARM are as follows: > + > + Xen binary should be loaded in memory below 2 TiB. > + > There are no exception on 64-bit ARM. This sentence needs to be dropped then. With that: Reviewed-by: Michal Orzel <michal.orzel@amd.com> ~Michal
On 24/10/2023 11:23, Michal Orzel wrote: > Hi Julien, Hi, > On 24/10/2023 12:09, Julien Grall wrote: >> >> >> From: Julien Grall <jgrall@amazon.com> >> >> In commit 9d267c049d92 ("xen/arm64: Rework the memory layout"), >> we decided to require Xen to be loaded below 5 TiB to simplify > s/5/2 Ah yes. I keep having 2 TiB. >> the logic to enable the MMU. The limit was decided based on >> how known platform boot plus some slack. >> >> We had a recent report that this is not sufficient on the AVA >> platform with a old firmware [1]. But the restriction is not >> going to change in Xen 4.18. So document the limit clearly >> in docs/misc/arm/booting.txt >> >> Signed-off-by: Julien Grall <jgrall@amazon.com> >> >> ---- > one less '-' Yes. I forgot to call 'sed -i 's/^----/---/' *.patch' before sending (I use ---- to prevent my pacthqueue management tool to strip anything after ---). > >> >> I couldn't find a nice way to document it in SUPPORT.md. So I decided >> to only document the restrict in docs/misc/arm/booting.txt for now. >> >> I also couldn't find any way from GRUB/UEFI (I didn't look much) to >> specify the loading address. >> --- >> docs/misc/arm/booting.txt | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/docs/misc/arm/booting.txt b/docs/misc/arm/booting.txt >> index 02f7bb65ec6d..c6bdeafe5e5b 100644 >> --- a/docs/misc/arm/booting.txt >> +++ b/docs/misc/arm/booting.txt >> @@ -21,6 +21,10 @@ The exceptions to this on 32-bit ARM are as follows: >> zImage protocol should still be used and not the stricter "raw >> (non-zImage)" protocol described in arm/Booting. >> >> +The exceptions to this on 64-bit ARM are as follows: >> + >> + Xen binary should be loaded in memory below 2 TiB. >> + >> There are no exception on 64-bit ARM. > This sentence needs to be dropped then. Whoops yes. > > With that: > Reviewed-by: Michal Orzel <michal.orzel@amd.com> Thanks! Cheers,
diff --git a/docs/misc/arm/booting.txt b/docs/misc/arm/booting.txt index 02f7bb65ec6d..c6bdeafe5e5b 100644 --- a/docs/misc/arm/booting.txt +++ b/docs/misc/arm/booting.txt @@ -21,6 +21,10 @@ The exceptions to this on 32-bit ARM are as follows: zImage protocol should still be used and not the stricter "raw (non-zImage)" protocol described in arm/Booting. +The exceptions to this on 64-bit ARM are as follows: + + Xen binary should be loaded in memory below 2 TiB. + There are no exception on 64-bit ARM. Booting Guests