| Message ID | 1454351417-23732-1-git-send-email-ard.biesheuvel@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Mon, Feb 01, 2016 at 07:30:17PM +0100, Ard Biesheuvel wrote: > void __init arm64_memblock_init(void) > { > const s64 linear_region_size = -(s64)PAGE_OFFSET; > @@ -215,24 +180,14 @@ void __init arm64_memblock_init(void) > if (memblock_end_of_DRAM() > linear_region_size) > memblock_remove(0, memblock_end_of_DRAM() - linear_region_size); > > + /* > + * Apply the memory limit if it was set. Since the kernel may be loaded > + * high up in memory, add back the kernel region that must be accessible > + * via the linear mapping. > + */ > if (memory_limit != (phys_addr_t)ULLONG_MAX) { > - u64 kbase = round_down(__pa(_text), MIN_KIMG_ALIGN); > - u64 kend = PAGE_ALIGN(__pa(_end)); > - u64 const sz_4g = 0x100000000UL; > - > - /* > - * Clip memory in order of preference: > - * - above the kernel and above 4 GB > - * - between 4 GB and the start of the kernel (if the kernel > - * is loaded high in memory) > - * - between the kernel and 4 GB (if the kernel is loaded > - * low in memory) > - * - below 4 GB > - */ > - clip_mem_range(max(sz_4g, kend), ULLONG_MAX); > - clip_mem_range(sz_4g, kbase); > - clip_mem_range(kend, sz_4g); > - clip_mem_range(0, min(kbase, sz_4g)); > + memblock_enforce_memory_limit(memory_limit); > + memblock_add(__pa(__init_begin), (u64)(_end - __init_begin)); Thanks, it looks much simpler now. However, loading the kernel 1GB higher with mem=1G fails somewhere during the KVM hyp initialisation. It works if I change the last line below to: memblock_add(__pa(_text), (u64)(_end - _text)); I can fold the change in. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On 2 February 2016 at 11:19, Catalin Marinas <catalin.marinas@arm.com> wrote: > On Mon, Feb 01, 2016 at 07:30:17PM +0100, Ard Biesheuvel wrote: >> void __init arm64_memblock_init(void) >> { >> const s64 linear_region_size = -(s64)PAGE_OFFSET; >> @@ -215,24 +180,14 @@ void __init arm64_memblock_init(void) >> if (memblock_end_of_DRAM() > linear_region_size) >> memblock_remove(0, memblock_end_of_DRAM() - linear_region_size); >> >> + /* >> + * Apply the memory limit if it was set. Since the kernel may be loaded >> + * high up in memory, add back the kernel region that must be accessible >> + * via the linear mapping. >> + */ >> if (memory_limit != (phys_addr_t)ULLONG_MAX) { >> - u64 kbase = round_down(__pa(_text), MIN_KIMG_ALIGN); >> - u64 kend = PAGE_ALIGN(__pa(_end)); >> - u64 const sz_4g = 0x100000000UL; >> - >> - /* >> - * Clip memory in order of preference: >> - * - above the kernel and above 4 GB >> - * - between 4 GB and the start of the kernel (if the kernel >> - * is loaded high in memory) >> - * - between the kernel and 4 GB (if the kernel is loaded >> - * low in memory) >> - * - below 4 GB >> - */ >> - clip_mem_range(max(sz_4g, kend), ULLONG_MAX); >> - clip_mem_range(sz_4g, kbase); >> - clip_mem_range(kend, sz_4g); >> - clip_mem_range(0, min(kbase, sz_4g)); >> + memblock_enforce_memory_limit(memory_limit); >> + memblock_add(__pa(__init_begin), (u64)(_end - __init_begin)); > > Thanks, it looks much simpler now. However, loading the kernel 1GB > higher with mem=1G fails somewhere during the KVM hyp initialisation. It > works if I change the last line below to: > > memblock_add(__pa(_text), (u64)(_end - _text)); > OK, that should work as well. I suppose the fact that mem= loses some of its accuracy is not an issue? If you need it to be exact, you should simply not load your kernel outside your mem= range ... > I can fold the change in. > OK _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On Tue, Feb 02, 2016 at 11:28:41AM +0100, Ard Biesheuvel wrote: > On 2 February 2016 at 11:19, Catalin Marinas <catalin.marinas@arm.com> wrote: > > On Mon, Feb 01, 2016 at 07:30:17PM +0100, Ard Biesheuvel wrote: > >> void __init arm64_memblock_init(void) > >> { > >> const s64 linear_region_size = -(s64)PAGE_OFFSET; > >> @@ -215,24 +180,14 @@ void __init arm64_memblock_init(void) > >> if (memblock_end_of_DRAM() > linear_region_size) > >> memblock_remove(0, memblock_end_of_DRAM() - linear_region_size); > >> > >> + /* > >> + * Apply the memory limit if it was set. Since the kernel may be loaded > >> + * high up in memory, add back the kernel region that must be accessible > >> + * via the linear mapping. > >> + */ > >> if (memory_limit != (phys_addr_t)ULLONG_MAX) { > >> - u64 kbase = round_down(__pa(_text), MIN_KIMG_ALIGN); > >> - u64 kend = PAGE_ALIGN(__pa(_end)); > >> - u64 const sz_4g = 0x100000000UL; > >> - > >> - /* > >> - * Clip memory in order of preference: > >> - * - above the kernel and above 4 GB > >> - * - between 4 GB and the start of the kernel (if the kernel > >> - * is loaded high in memory) > >> - * - between the kernel and 4 GB (if the kernel is loaded > >> - * low in memory) > >> - * - below 4 GB > >> - */ > >> - clip_mem_range(max(sz_4g, kend), ULLONG_MAX); > >> - clip_mem_range(sz_4g, kbase); > >> - clip_mem_range(kend, sz_4g); > >> - clip_mem_range(0, min(kbase, sz_4g)); > >> + memblock_enforce_memory_limit(memory_limit); > >> + memblock_add(__pa(__init_begin), (u64)(_end - __init_begin)); > > > > Thanks, it looks much simpler now. However, loading the kernel 1GB > > higher with mem=1G fails somewhere during the KVM hyp initialisation. It > > works if I change the last line below to: > > > > memblock_add(__pa(_text), (u64)(_end - _text)); > > OK, that should work as well. > > I suppose the fact that mem= loses some of its accuracy is not an > issue? If you need it to be exact, you should simply not load your > kernel outside your mem= range ... I'm not worried about accuracy. We could avoid freeing the init mem if the kernel is outside the memory_limit range but I don't really think it's worth. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index e8e853a1024c..361c91209031 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -160,41 +160,6 @@ static int __init early_mem(char *p) } early_param("mem", early_mem); -/* - * clip_mem_range() - remove memblock memory between @min and @max until - * we meet the limit in 'memory_limit'. - */ -static void __init clip_mem_range(u64 min, u64 max) -{ - u64 mem_size, to_remove; - int i; - -again: - mem_size = memblock_phys_mem_size(); - if (mem_size <= memory_limit || max <= min) - return; - - to_remove = mem_size - memory_limit; - - for (i = memblock.memory.cnt - 1; i >= 0; i--) { - struct memblock_region *r = memblock.memory.regions + i; - u64 start = max(min, r->base); - u64 end = min(max, r->base + r->size); - - if (start >= max || end <= min) - continue; - - if (end > min) { - u64 size = min(to_remove, end - max(start, min)); - - memblock_remove(end - size, size); - } else { - memblock_remove(start, min(max - start, to_remove)); - } - goto again; - } -} - void __init arm64_memblock_init(void) { const s64 linear_region_size = -(s64)PAGE_OFFSET; @@ -215,24 +180,14 @@ void __init arm64_memblock_init(void) if (memblock_end_of_DRAM() > linear_region_size) memblock_remove(0, memblock_end_of_DRAM() - linear_region_size); + /* + * Apply the memory limit if it was set. Since the kernel may be loaded + * high up in memory, add back the kernel region that must be accessible + * via the linear mapping. + */ if (memory_limit != (phys_addr_t)ULLONG_MAX) { - u64 kbase = round_down(__pa(_text), MIN_KIMG_ALIGN); - u64 kend = PAGE_ALIGN(__pa(_end)); - u64 const sz_4g = 0x100000000UL; - - /* - * Clip memory in order of preference: - * - above the kernel and above 4 GB - * - between 4 GB and the start of the kernel (if the kernel - * is loaded high in memory) - * - between the kernel and 4 GB (if the kernel is loaded - * low in memory) - * - below 4 GB - */ - clip_mem_range(max(sz_4g, kend), ULLONG_MAX); - clip_mem_range(sz_4g, kbase); - clip_mem_range(kend, sz_4g); - clip_mem_range(0, min(kbase, sz_4g)); + memblock_enforce_memory_limit(memory_limit); + memblock_add(__pa(__init_begin), (u64)(_end - __init_begin)); } /*
Rather than implementing our own elaborate logic to clip the memory ranges in order of preference, use the generic memblock_enforce_memory_limit() as before, and explicitly add back that part of the kernel that needs to be accessible via the linear mapping as well as via the kernel mapping. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- arch/arm64/mm/init.c | 59 +++++++--------------------------------------------- 1 file changed, 7 insertions(+), 52 deletions(-) -- 2.5.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel