On 26/07/2019 15:22, Roger Pau Monné wrote: > On Fri, Jul 26, 2019 at 02:52:39PM +0100, Andrew Cooper wrote: >> Future changes are going to need to page align some percpu data. >> >> This means that the percpu area needs suiably aligning in the BSS so CPU0 has >> correctly aligned data. Shuffle the exact link order of items within the BSS >> to give .bss.percpu.page_aligned appropriate alignment. >> >> Additionally, introduce DEFINE_PER_CPU_PAGE_ALIGNED() >> >> Signed-off-by: Andrew Cooper <andrew.coop...@citrix.com> >> --- >> CC: Jan Beulich <jbeul...@suse.com> >> CC: Wei Liu <w...@xen.org> >> CC: Roger Pau Monné <roger....@citrix.com> >> CC: Stefano Stabellini <sstabell...@kernel.org> >> CC: Julien Grall <julien.gr...@arm.com> >> CC: Volodymyr Babchuk <volodymyr_babc...@epam.com> >> --- >> xen/arch/arm/xen.lds.S | 5 +++-- >> xen/arch/x86/xen.lds.S | 5 +++-- >> xen/include/xen/percpu.h | 2 ++ >> 3 files changed, 8 insertions(+), 4 deletions(-) >> >> diff --git a/xen/arch/arm/xen.lds.S b/xen/arch/arm/xen.lds.S >> index 12c107f45d..07cbdf2543 100644 >> --- a/xen/arch/arm/xen.lds.S >> +++ b/xen/arch/arm/xen.lds.S >> @@ -201,14 +201,15 @@ SECTIONS >> *(.bss.stack_aligned) >> . = ALIGN(PAGE_SIZE); >> *(.bss.page_aligned) >> - *(.bss) >> - . = ALIGN(SMP_CACHE_BYTES); > Don't you also need a: > > . = ALIGN(PAGE_SIZE); > > here?
No, (I don't think so). > Or is the size of .bss.page_aligned also aligned to page size? Every object inside .bss.page_aligned should have suitable (i.e. multiple of) size and alignment. Without this, things will break. ~Andrew _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
