| Message ID | 20190514122456.28559-18-julien.grall@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | xen/arm: Clean-up & fixes in boot/mm code | expand |
On Tue, 14 May 2019, Julien Grall wrote: > Since commit f60658c6ae "xen/arm: Stop relocating Xen", the function > setup_page_tables() does not require any information from the FDT. > > So the initialization of the page-tables can be done much earlier in the > boot process. The earliest setup_page_tables() can be called is after > traps have been initialized, so we can get backtrace if an error > occurred. > > Moving the initialization of the page-tables also avoid the dance to map > the FDT again in the new set of page-tables. > > Signed-off-by: Julien Grall <julien.grall@arm.com> > Reviewed-by: Andrii Anisov <andrii_anisov@epam.com> > > --- > Changes in v2: > - Add Andrii's reviewed-by > --- > xen/arch/arm/mm.c | 12 +++--------- > xen/arch/arm/setup.c | 4 ++-- > 2 files changed, 5 insertions(+), 11 deletions(-) > > diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c > index 7502a14760..eacc1647e0 100644 > --- a/xen/arch/arm/mm.c > +++ b/xen/arch/arm/mm.c > @@ -550,7 +550,7 @@ static inline lpae_t pte_of_xenaddr(vaddr_t va) > return mfn_to_xen_entry(maddr_to_mfn(ma), MT_NORMAL); > } > > -/* Map the FDT in the early boot page table */ > +/* Map the FDT in the runtime page table */ I think you can drop this comment now. In any case: Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> > void * __init early_fdt_map(paddr_t fdt_paddr) > { > /* We are using 2MB superpage for mapping the FDT */ > @@ -573,7 +573,7 @@ void * __init early_fdt_map(paddr_t fdt_paddr) > /* The FDT is mapped using 2MB superpage */ > BUILD_BUG_ON(BOOT_FDT_VIRT_START % SZ_2M); > > - create_mappings(boot_second, BOOT_FDT_VIRT_START, paddr_to_pfn(base_paddr), > + create_mappings(xen_second, BOOT_FDT_VIRT_START, paddr_to_pfn(base_paddr), > SZ_2M >> PAGE_SHIFT, SZ_2M); > > offset = fdt_paddr % SECOND_SIZE; > @@ -588,7 +588,7 @@ void * __init early_fdt_map(paddr_t fdt_paddr) > > if ( (offset + size) > SZ_2M ) > { > - create_mappings(boot_second, BOOT_FDT_VIRT_START + SZ_2M, > + create_mappings(xen_second, BOOT_FDT_VIRT_START + SZ_2M, > paddr_to_pfn(base_paddr + SZ_2M), > SZ_2M >> PAGE_SHIFT, SZ_2M); > } > @@ -699,12 +699,6 @@ void __init setup_pagetables(unsigned long boot_phys_offset) > pte.pt.table = 1; > xen_second[second_table_offset(FIXMAP_ADDR(0))] = pte; > > - /* ... DTB */ > - pte = boot_second[second_table_offset(BOOT_FDT_VIRT_START)]; > - xen_second[second_table_offset(BOOT_FDT_VIRT_START)] = pte; > - pte = boot_second[second_table_offset(BOOT_FDT_VIRT_START + SZ_2M)]; > - xen_second[second_table_offset(BOOT_FDT_VIRT_START + SZ_2M)] = pte; > - > #ifdef CONFIG_ARM_64 > ttbr = (uintptr_t) xen_pgtable + phys_offset; > #else > diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c > index 2f714d8b37..889da40d8d 100644 > --- a/xen/arch/arm/setup.c > +++ b/xen/arch/arm/setup.c > @@ -759,6 +759,8 @@ void __init start_xen(unsigned long boot_phys_offset, > /* Initialize traps early allow us to get backtrace when an error occurred */ > init_traps(); > > + setup_pagetables(boot_phys_offset); > + > smp_clear_cpu_maps(); > > device_tree_flattened = early_fdt_map(fdt_paddr); > @@ -780,8 +782,6 @@ void __init start_xen(unsigned long boot_phys_offset, > (paddr_t)(uintptr_t)(_end - _start + 1), false); > BUG_ON(!xen_bootmodule); > > - setup_pagetables(boot_phys_offset); > - > setup_mm(fdt_paddr, fdt_size); > > /* Parse the ACPI tables for possible boot-time configuration */ > -- > 2.11.0 >
Hi Stefano, On 05/06/2019 00:12, Stefano Stabellini wrote: > On Tue, 14 May 2019, Julien Grall wrote: >> Since commit f60658c6ae "xen/arm: Stop relocating Xen", the function >> setup_page_tables() does not require any information from the FDT. >> >> So the initialization of the page-tables can be done much earlier in the >> boot process. The earliest setup_page_tables() can be called is after >> traps have been initialized, so we can get backtrace if an error >> occurred. >> >> Moving the initialization of the page-tables also avoid the dance to map >> the FDT again in the new set of page-tables. >> >> Signed-off-by: Julien Grall <julien.grall@arm.com> >> Reviewed-by: Andrii Anisov <andrii_anisov@epam.com> >> >> --- >> Changes in v2: >> - Add Andrii's reviewed-by >> --- >> xen/arch/arm/mm.c | 12 +++--------- >> xen/arch/arm/setup.c | 4 ++-- >> 2 files changed, 5 insertions(+), 11 deletions(-) >> >> diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c >> index 7502a14760..eacc1647e0 100644 >> --- a/xen/arch/arm/mm.c >> +++ b/xen/arch/arm/mm.c >> @@ -550,7 +550,7 @@ static inline lpae_t pte_of_xenaddr(vaddr_t va) >> return mfn_to_xen_entry(maddr_to_mfn(ma), MT_NORMAL); >> } >> >> -/* Map the FDT in the early boot page table */ >> +/* Map the FDT in the runtime page table */ > > I think you can drop this comment now. Good point, the more the plan is to have only one set of page-tables. > > In any case: > > Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Thank you for the review! Cheers,
diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c index 7502a14760..eacc1647e0 100644 --- a/xen/arch/arm/mm.c +++ b/xen/arch/arm/mm.c @@ -550,7 +550,7 @@ static inline lpae_t pte_of_xenaddr(vaddr_t va) return mfn_to_xen_entry(maddr_to_mfn(ma), MT_NORMAL); } -/* Map the FDT in the early boot page table */ +/* Map the FDT in the runtime page table */ void * __init early_fdt_map(paddr_t fdt_paddr) { /* We are using 2MB superpage for mapping the FDT */ @@ -573,7 +573,7 @@ void * __init early_fdt_map(paddr_t fdt_paddr) /* The FDT is mapped using 2MB superpage */ BUILD_BUG_ON(BOOT_FDT_VIRT_START % SZ_2M); - create_mappings(boot_second, BOOT_FDT_VIRT_START, paddr_to_pfn(base_paddr), + create_mappings(xen_second, BOOT_FDT_VIRT_START, paddr_to_pfn(base_paddr), SZ_2M >> PAGE_SHIFT, SZ_2M); offset = fdt_paddr % SECOND_SIZE; @@ -588,7 +588,7 @@ void * __init early_fdt_map(paddr_t fdt_paddr) if ( (offset + size) > SZ_2M ) { - create_mappings(boot_second, BOOT_FDT_VIRT_START + SZ_2M, + create_mappings(xen_second, BOOT_FDT_VIRT_START + SZ_2M, paddr_to_pfn(base_paddr + SZ_2M), SZ_2M >> PAGE_SHIFT, SZ_2M); } @@ -699,12 +699,6 @@ void __init setup_pagetables(unsigned long boot_phys_offset) pte.pt.table = 1; xen_second[second_table_offset(FIXMAP_ADDR(0))] = pte; - /* ... DTB */ - pte = boot_second[second_table_offset(BOOT_FDT_VIRT_START)]; - xen_second[second_table_offset(BOOT_FDT_VIRT_START)] = pte; - pte = boot_second[second_table_offset(BOOT_FDT_VIRT_START + SZ_2M)]; - xen_second[second_table_offset(BOOT_FDT_VIRT_START + SZ_2M)] = pte; - #ifdef CONFIG_ARM_64 ttbr = (uintptr_t) xen_pgtable + phys_offset; #else diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c index 2f714d8b37..889da40d8d 100644 --- a/xen/arch/arm/setup.c +++ b/xen/arch/arm/setup.c @@ -759,6 +759,8 @@ void __init start_xen(unsigned long boot_phys_offset, /* Initialize traps early allow us to get backtrace when an error occurred */ init_traps(); + setup_pagetables(boot_phys_offset); + smp_clear_cpu_maps(); device_tree_flattened = early_fdt_map(fdt_paddr); @@ -780,8 +782,6 @@ void __init start_xen(unsigned long boot_phys_offset, (paddr_t)(uintptr_t)(_end - _start + 1), false); BUG_ON(!xen_bootmodule); - setup_pagetables(boot_phys_offset); - setup_mm(fdt_paddr, fdt_size); /* Parse the ACPI tables for possible boot-time configuration */