| Message ID | 1371229044-3970-1-git-send-email-mark.rutland@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Jun 14, 2013 at 05:57:24PM +0100, Mark Rutland wrote: > In e651eab0af: "ARM: 7677/1: LPAE: Fix mapping in alloc_init_section for > unaligned addresses", the pmd flushing was broken when split out to > map_init_section. At the end of the final iteration of the while loop, > pmd will point at the pmd_t immediately after the pmds we updated, and > thus flush_pmd_entry(pmd) won't flush the newly modified pmds. This has > been observed to prevent an 11MPCore system from booting. > > This patch fixes this by remembering the address of the first pmd we > update and using this as the argument to flush_pmd_entry. > > Signed-off-by: Mark Rutland <mark.rutland@arm.com> > Cc: R Sricharan <r.sricharan@ti.com> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Christoffer Dall <cdall@cs.columbia.edu> > Cc: Russell King <rmk+kernel@arm.linux.org.uk> > Cc: stable@vger.kernel.org > --- > Since v1: > * Take the incremented value of pmd for !LPAE. > * Comment why only one cache flush is necessary. > > arch/arm/mm/mmu.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c > index e0d8565..1c66f51 100644 > --- a/arch/arm/mm/mmu.c > +++ b/arch/arm/mm/mmu.c > @@ -620,6 +620,7 @@ static void __init map_init_section(pmd_t *pmd, unsigned long addr, > unsigned long end, phys_addr_t phys, > const struct mem_type *type) > { > + pmd_t *p; > #ifndef CONFIG_ARM_LPAE > /* > * In classic MMU format, puds and pmds are folded in to > @@ -633,12 +634,18 @@ static void __init map_init_section(pmd_t *pmd, unsigned long addr, > if (addr & SECTION_SIZE) > pmd++; > #endif > + p = pmd; > + > do { > *pmd = __pmd(phys | type->prot_sect); > phys += SECTION_SIZE; > } while (pmd++, addr += SECTION_SIZE, addr != end); > > - flush_pmd_entry(pmd); > + /* > + * We expect a minimum cache line of 8 bytes, so this will flush both > + * pmd entries with classic tables, and will be a nop for LPAE systems. > + */ > + flush_pmd_entry(p); > } > > static void __init alloc_init_pmd(pud_t *pud, unsigned long addr, > -- Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
On Fri, Jun 14, 2013 at 05:57:24PM +0100, Mark Rutland wrote: > In e651eab0af: "ARM: 7677/1: LPAE: Fix mapping in alloc_init_section for > unaligned addresses", the pmd flushing was broken when split out to > map_init_section. At the end of the final iteration of the while loop, > pmd will point at the pmd_t immediately after the pmds we updated, and > thus flush_pmd_entry(pmd) won't flush the newly modified pmds. This has > been observed to prevent an 11MPCore system from booting. > > This patch fixes this by remembering the address of the first pmd we > update and using this as the argument to flush_pmd_entry. > > Signed-off-by: Mark Rutland <mark.rutland@arm.com> > Cc: R Sricharan <r.sricharan@ti.com> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Christoffer Dall <cdall@cs.columbia.edu> > Cc: Russell King <rmk+kernel@arm.linux.org.uk> > Cc: stable@vger.kernel.org Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index e0d8565..1c66f51 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -620,6 +620,7 @@ static void __init map_init_section(pmd_t *pmd, unsigned long addr, unsigned long end, phys_addr_t phys, const struct mem_type *type) { + pmd_t *p; #ifndef CONFIG_ARM_LPAE /* * In classic MMU format, puds and pmds are folded in to @@ -633,12 +634,18 @@ static void __init map_init_section(pmd_t *pmd, unsigned long addr, if (addr & SECTION_SIZE) pmd++; #endif + p = pmd; + do { *pmd = __pmd(phys | type->prot_sect); phys += SECTION_SIZE; } while (pmd++, addr += SECTION_SIZE, addr != end); - flush_pmd_entry(pmd); + /* + * We expect a minimum cache line of 8 bytes, so this will flush both + * pmd entries with classic tables, and will be a nop for LPAE systems. + */ + flush_pmd_entry(p); } static void __init alloc_init_pmd(pud_t *pud, unsigned long addr,
In e651eab0af: "ARM: 7677/1: LPAE: Fix mapping in alloc_init_section for unaligned addresses", the pmd flushing was broken when split out to map_init_section. At the end of the final iteration of the while loop, pmd will point at the pmd_t immediately after the pmds we updated, and thus flush_pmd_entry(pmd) won't flush the newly modified pmds. This has been observed to prevent an 11MPCore system from booting. This patch fixes this by remembering the address of the first pmd we update and using this as the argument to flush_pmd_entry. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: R Sricharan <r.sricharan@ti.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoffer Dall <cdall@cs.columbia.edu> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: stable@vger.kernel.org --- Since v1: * Take the incremented value of pmd for !LPAE. * Comment why only one cache flush is necessary. arch/arm/mm/mmu.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)