| Message ID | 1439830867-14935-3-git-send-email-msalter@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Aug 17, 2015 at 06:01:06PM +0100, Mark Salter wrote: > The use of mem= could leave part or all of the initrd outside of > the kernel linear map. This will lead to an error when unpacking > the initrd and a probable failure to boot. This patch catches that > situation and relocates the initrd to be fully within the linear > map. > > Signed-off-by: Mark Salter <msalter@redhat.com> > --- > arch/arm64/kernel/setup.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 62 insertions(+) Looks good to me: Acked-by: Will Deacon <will.deacon@arm.com> This series should replace the version that Andrew has currently got in linux-next. Will > diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c > index f3067d4..40a894e 100644 > --- a/arch/arm64/kernel/setup.c > +++ b/arch/arm64/kernel/setup.c > @@ -359,6 +359,67 @@ static void __init request_standard_resources(void) > } > } > > +#ifdef CONFIG_BLK_DEV_INITRD > +/* > + * Relocate initrd if it is not completely within the linear mapping. > + * This would be the case if mem= cuts out all or part of it. > + */ > +static void __init relocate_initrd(void) > +{ > + phys_addr_t orig_start = __virt_to_phys(initrd_start); > + phys_addr_t orig_end = __virt_to_phys(initrd_end); > + phys_addr_t ram_end = memblock_end_of_DRAM(); > + phys_addr_t new_start; > + unsigned long size, to_free = 0; > + void *dest; > + > + if (orig_end <= ram_end) > + return; > + > + /* > + * Any of the original initrd which overlaps the linear map should > + * be freed after relocating. > + */ > + if (orig_start < ram_end) > + to_free = ram_end - orig_start; > + > + size = orig_end - orig_start; > + > + /* initrd needs to be relocated completely inside linear mapping */ > + new_start = memblock_find_in_range(0, PFN_PHYS(max_pfn), > + size, PAGE_SIZE); > + if (!new_start) > + panic("Cannot relocate initrd of size %ld\n", size); > + memblock_reserve(new_start, size); > + > + initrd_start = __phys_to_virt(new_start); > + initrd_end = initrd_start + size; > + > + pr_info("Moving initrd from [%llx-%llx] to [%llx-%llx]\n", > + orig_start, orig_start + size - 1, > + new_start, new_start + size - 1); > + > + dest = (void *)initrd_start; > + > + if (to_free) { > + memcpy(dest, (void *)__phys_to_virt(orig_start), to_free); > + dest += to_free; > + } > + > + copy_from_early_mem(dest, orig_start + to_free, size - to_free); > + > + if (to_free) { > + pr_info("Freeing original RAMDISK from [%llx-%llx]\n", > + orig_start, orig_start + to_free - 1); > + memblock_free(orig_start, to_free); > + } > +} > +#else > +static inline void __init relocate_initrd(void) > +{ > +} > +#endif > + > u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID }; > > void __init setup_arch(char **cmdline_p) > @@ -392,6 +453,7 @@ void __init setup_arch(char **cmdline_p) > acpi_boot_table_init(); > > paging_init(); > + relocate_initrd(); > request_standard_resources(); > > early_ioremap_reset(); > -- > 2.4.3 >
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index f3067d4..40a894e 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -359,6 +359,67 @@ static void __init request_standard_resources(void) } } +#ifdef CONFIG_BLK_DEV_INITRD +/* + * Relocate initrd if it is not completely within the linear mapping. + * This would be the case if mem= cuts out all or part of it. + */ +static void __init relocate_initrd(void) +{ + phys_addr_t orig_start = __virt_to_phys(initrd_start); + phys_addr_t orig_end = __virt_to_phys(initrd_end); + phys_addr_t ram_end = memblock_end_of_DRAM(); + phys_addr_t new_start; + unsigned long size, to_free = 0; + void *dest; + + if (orig_end <= ram_end) + return; + + /* + * Any of the original initrd which overlaps the linear map should + * be freed after relocating. + */ + if (orig_start < ram_end) + to_free = ram_end - orig_start; + + size = orig_end - orig_start; + + /* initrd needs to be relocated completely inside linear mapping */ + new_start = memblock_find_in_range(0, PFN_PHYS(max_pfn), + size, PAGE_SIZE); + if (!new_start) + panic("Cannot relocate initrd of size %ld\n", size); + memblock_reserve(new_start, size); + + initrd_start = __phys_to_virt(new_start); + initrd_end = initrd_start + size; + + pr_info("Moving initrd from [%llx-%llx] to [%llx-%llx]\n", + orig_start, orig_start + size - 1, + new_start, new_start + size - 1); + + dest = (void *)initrd_start; + + if (to_free) { + memcpy(dest, (void *)__phys_to_virt(orig_start), to_free); + dest += to_free; + } + + copy_from_early_mem(dest, orig_start + to_free, size - to_free); + + if (to_free) { + pr_info("Freeing original RAMDISK from [%llx-%llx]\n", + orig_start, orig_start + to_free - 1); + memblock_free(orig_start, to_free); + } +} +#else +static inline void __init relocate_initrd(void) +{ +} +#endif + u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID }; void __init setup_arch(char **cmdline_p) @@ -392,6 +453,7 @@ void __init setup_arch(char **cmdline_p) acpi_boot_table_init(); paging_init(); + relocate_initrd(); request_standard_resources(); early_ioremap_reset();
The use of mem= could leave part or all of the initrd outside of the kernel linear map. This will lead to an error when unpacking the initrd and a probable failure to boot. This patch catches that situation and relocates the initrd to be fully within the linear map. Signed-off-by: Mark Salter <msalter@redhat.com> --- arch/arm64/kernel/setup.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+)