x86, pat: ioremap to follow same PAT restrictions as other PAT users (279e669b) · Commits · 戴 / test

ioremap has this hard-coded check for new type and requested type. That check differs from other PAT users like /dev/mem mmap, remap_pfn_range in only one condition where requested type is UC_MINUS and new type is WC. Under that condition, ioremap fails. But other PAT interfaces succeed with a WC mapping. Change to make ioremap be in sync with other PAT APIs and use the same macro as others. Also changes the error print to KERN_ERR instead of pr_debug. Signed-off-by:

Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by:

Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by:

H. Peter Anvin <hpa@zytor.com>

arch/x86/mm/ioremap.c

+3 −14

Original line number	Diff line number	Diff line
		@@ -228,24 +228,13 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
		retval = reserve_memtype(phys_addr, (u64)phys_addr + size,
		prot_val, &new_prot_val);
		if (retval) {
		pr_debug("Warning: reserve_memtype returned %d\n", retval);
		printk(KERN_ERR "ioremap reserve_memtype failed %d\n", retval);
		return NULL;
		}

		if (prot_val != new_prot_val) {
		/*
		* Do not fallback to certain memory types with certain
		* requested type:
		* - request is uc-, return cannot be write-back
		* - request is uc-, return cannot be write-combine
		* - request is write-combine, return cannot be write-back
		*/
		if ((prot_val == _PAGE_CACHE_UC_MINUS &&
		(new_prot_val == _PAGE_CACHE_WB \|\|
		new_prot_val == _PAGE_CACHE_WC)) \|\|
		(prot_val == _PAGE_CACHE_WC &&
		new_prot_val == _PAGE_CACHE_WB)) {
		pr_debug(
		if (!is_new_memtype_allowed(prot_val, new_prot_val)) {
		printk(KERN_ERR
		"ioremap error for 0x%llx-0x%llx, requested 0x%lx, got 0x%lx\n",
		(unsigned long long)phys_addr,
		(unsigned long long)(phys_addr + size),

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