ARM: mm: cleanup checks for membank overlap with vmalloc area (adf2e9fd) · Commits · 戴 / test

On Keystone platforms, physical memory is entirely outside the 32-bit addressible range. Therefore, the (bank->start > ULONG_MAX) check below marks the entire system memory as highmem, and this causes unpleasentness all over. This patch eliminates the extra bank start check (against ULONG_MAX) by checking bank->start against the physical address corresponding to vmalloc_min instead. In the process, this patch also cleans up parts of the highmem sanity check code by removing what has now become a redundant check for banks that entirely overlap with the vmalloc range. Signed-off-by:

Cyril Chemparathy <cyril@ti.com> Signed-off-by:

Vitaly Andrianov <vitalya@ti.com> Acked-by:

Nicolas Pitre <nico@linaro.org> Tested-by:

Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by:

Subash Patel <subash.rp@samsung.com> Signed-off-by:

Will Deacon <will.deacon@arm.com>

arch/arm/mm/mmu.c

+1 −18

Original line number	Diff line number	Diff line
		@@ -994,15 +994,12 @@ void __init sanity_check_meminfo(void)
		struct membank *bank = &meminfo.bank[j];
		*bank = meminfo.bank[i];

		if (bank->start > ULONG_MAX)
		highmem = 1;

		#ifdef CONFIG_HIGHMEM
		if (bank->start >= vmalloc_limit)
		highmem = 1;

		bank->highmem = highmem;

		#ifdef CONFIG_HIGHMEM
		/*
		* Split those memory banks which are partially overlapping
		* the vmalloc area greatly simplifying things later.
		@@ -1025,8 +1022,6 @@ void __init sanity_check_meminfo(void)
		bank->size = vmalloc_limit - bank->start;
		}
		#else
		bank->highmem = highmem;

		/*
		* Highmem banks not allowed with !CONFIG_HIGHMEM.
		*/
		@@ -1038,18 +1033,6 @@ void __init sanity_check_meminfo(void)
		continue;
		}

		/*
		* Check whether this memory bank would entirely overlap
		* the vmalloc area.
		*/
		if (bank->start >= vmalloc_limit) {
		printk(KERN_NOTICE "Ignoring RAM at %.8llx-%.8llx "
		"(vmalloc region overlap).\n",
		(unsigned long long)bank->start,
		(unsigned long long)bank->start + bank->size - 1);
		continue;
		}

		/*
		* Check whether this memory bank would partially overlap
		* the vmalloc area.

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