| Message ID | 20201119190751.22345-2-julien@xen.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | xen/arm: mm: Add limited support for superpages | expand |
Hi Julien, > On 19 Nov 2020, at 19:07, Julien Grall <julien@xen.org> wrote: > > From: Stefano Stabellini <sstabellini@kernel.org> > > There is no need to have a special case for CPU0 when converting the > page-table virtual address into a physical address. The helper > virt_to_maddr() is able to translate any address as long as the root > page-tables is mapped in the virtual address. This is the case for all > the CPUs at the moment. > > So use the same BUG_ON() regardless the CPU. > > Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com> > [julien: Rework the commit message] > Signed-off-by: Julien Grall <jgrall@amazon.com> Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com> Cheers Bertrand > > --- > > I went back through the conversation in [1] regarding the issue when > loading Xen below 2MB on Arm32. The example provided is wrong because to > find the physical address, we need to add 'phys_offset', not substract. > > So I removed the comment regarding the code was buggy. > > [1] https://marc.info/?l=xen-devel&m=157081398022401 > --- > xen/arch/arm/mm.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) > > diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c > index 9c4b26bf079b..4dd886f7c80d 100644 > --- a/xen/arch/arm/mm.c > +++ b/xen/arch/arm/mm.c > @@ -284,10 +284,7 @@ void dump_hyp_walk(vaddr_t addr) > "on CPU%d via TTBR 0x%016"PRIx64"\n", > addr, smp_processor_id(), ttbr); > > - if ( smp_processor_id() == 0 ) > - BUG_ON( (lpae_t *)(unsigned long)(ttbr - phys_offset) != pgtable ); > - else > - BUG_ON( virt_to_maddr(pgtable) != ttbr ); > + BUG_ON( virt_to_maddr(pgtable) != ttbr ); > dump_pt_walk(ttbr, addr, HYP_PT_ROOT_LEVEL, 1); > } > > -- > 2.17.1 >
On 19/11/2020 19:07, Julien Grall wrote: > From: Stefano Stabellini <sstabellini@kernel.org> > > There is no need to have a special case for CPU0 when converting the > page-table virtual address into a physical address. The helper > virt_to_maddr() is able to translate any address as long as the root > page-tables is mapped in the virtual address. This is the case for all > the CPUs at the moment. > > So use the same BUG_ON() regardless the CPU. > > Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com> > [julien: Rework the commit message] > Signed-off-by: Julien Grall <jgrall@amazon.com> > > --- > > I went back through the conversation in [1] regarding the issue when > loading Xen below 2MB on Arm32. The example provided is wrong because to > find the physical address, we need to add 'phys_offset', not substract. > > So I removed the comment regarding the code was buggy. > > [1] https://marc.info/?l=xen-devel&m=157081398022401 Stefano, can you confirm that you are happy with the new commit message? Cheers,
On Sat, 28 Nov 2020, Julien Grall wrote: > On 19/11/2020 19:07, Julien Grall wrote: > > From: Stefano Stabellini <sstabellini@kernel.org> > > > > There is no need to have a special case for CPU0 when converting the > > page-table virtual address into a physical address. The helper > > virt_to_maddr() is able to translate any address as long as the root > > page-tables is mapped in the virtual address. This is the case for all > > the CPUs at the moment. > > > > So use the same BUG_ON() regardless the CPU. > > > > Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com> > > [julien: Rework the commit message] > > Signed-off-by: Julien Grall <jgrall@amazon.com> > > > > --- > > > > I went back through the conversation in [1] regarding the issue when > > loading Xen below 2MB on Arm32. The example provided is wrong because to > > find the physical address, we need to add 'phys_offset', not substract. > > > > So I removed the comment regarding the code was buggy. > > > > [1] https://marc.info/?l=xen-devel&m=157081398022401 > > Stefano, can you confirm that you are happy with the new commit message? Yes, that's OK
diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c index 9c4b26bf079b..4dd886f7c80d 100644 --- a/xen/arch/arm/mm.c +++ b/xen/arch/arm/mm.c @@ -284,10 +284,7 @@ void dump_hyp_walk(vaddr_t addr) "on CPU%d via TTBR 0x%016"PRIx64"\n", addr, smp_processor_id(), ttbr); - if ( smp_processor_id() == 0 ) - BUG_ON( (lpae_t *)(unsigned long)(ttbr - phys_offset) != pgtable ); - else - BUG_ON( virt_to_maddr(pgtable) != ttbr ); + BUG_ON( virt_to_maddr(pgtable) != ttbr ); dump_pt_walk(ttbr, addr, HYP_PT_ROOT_LEVEL, 1); }