search for: fixaddr_top

On Thu, Jun 08 2023 at 17:33, Hou Wenlong wrote: > On Wed, Jun 07, 2023 at 08:49:15PM +0800, Dave Hansen wrote: >> What problems does this patch set solve? How might that solution be >> visible to end users? Why is this problem important to you? > > We want to build the kernel as PIE and allow the kernel image area, > including the fixmap area, to be placed at any virtual

Rusty Russell wrote: > Chris: [RFC PATCH 12/33] Change __FIXADDR_TOP to leave room for the hypervisor. > - Replace with dynamic (Geerd) patch, put in paravirt_ops structure. > I'm looking at this, and I'm not sure that there needs to be a void (*set_fixmap_top)(unsigned long top) entry in paravirt ops. It seems to me that the hypervisor's i...

...D worth */ -#define KM_TYPE_NR ((FIXMAP_SIZE >> PAGE_SHIFT)/NR_CPUS) -#define FIXMAP_ADDR(nr) (FIXMAP_BASE + ((nr) << PAGE_SHIFT)) + +#define FIX_KMAP_SLOTS (KM_MAX_IDX * NR_CPUS) +#define FIX_KMAP_BEGIN (0UL) +#define FIX_KMAP_END ((FIX_KMAP_BEGIN + FIX_KMAP_SLOTS) - 1) + +#define FIXADDR_TOP (FIXMAP_BASE + (FIX_KMAP_END << PAGE_SHIFT)) + +/* + * This should be converted to the asm-generic version, but of course this + * is needlessly different from all other architectures. Sigh - tglx + */ +#define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT)) +#define __virt_to_fix...

...M - " pkmap : 0x%08lx - 0x%08lx (%4ld kB)\n" -#endif " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" " lowmem : 0x%08lx - 0x%08lx (%4ld MB) (cached)\n" #ifdef CONFIG_UNCACHED_MAPPING @@ -376,11 +373,6 @@ void __init mem_init(void) FIXADDR_START, FIXADDR_TOP, (FIXADDR_TOP - FIXADDR_START) >> 10, -#ifdef CONFIG_HIGHMEM - PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE, - (LAST_PKMAP*PAGE_SIZE) >> 10, -#endif - (unsigned long)VMALLOC_START, VMALLOC_END, (VMALLOC_END - VMALLOC_START) >> 20,

...lude <linux/pagemap.h> #include <linux/spinlock.h> +#include <linux/module.h> #include <asm/system.h> #include <asm/pgtable.h> @@ -138,6 +139,10 @@ void set_pmd_pfn(unsigned long vaddr, un __flush_tlb_one(vaddr); } +static int nr_fixmaps = 0; +unsigned long __FIXADDR_TOP = 0xfffff000; +EXPORT_SYMBOL(__FIXADDR_TOP); + void __set_fixmap (enum fixed_addresses idx, unsigned long phys, pgprot_t flags) { unsigned long address = __fix_to_virt(idx); @@ -147,6 +152,13 @@ void __set_fixmap (enum fixed_addresses return; } set_pte_pfn(address, phys >> PAGE_SH...

...lude <linux/pagemap.h> #include <linux/spinlock.h> +#include <linux/module.h> #include <asm/system.h> #include <asm/pgtable.h> @@ -138,6 +139,10 @@ void set_pmd_pfn(unsigned long vaddr, un __flush_tlb_one(vaddr); } +static int nr_fixmaps = 0; +unsigned long __FIXADDR_TOP = 0xfffff000; +EXPORT_SYMBOL(__FIXADDR_TOP); + void __set_fixmap (enum fixed_addresses idx, unsigned long phys, pgprot_t flags) { unsigned long address = __fix_to_virt(idx); @@ -147,6 +152,13 @@ void __set_fixmap (enum fixed_addresses return; } set_pte_pfn(address, phys >> PAGE_SH...

...High Memory Support" depends on MMU + select KMAP_LOCAL help The address space of ARM processors is only 4 Gigabytes large and it has to accommodate user address space, kernel address --- a/arch/arm/include/asm/fixmap.h +++ b/arch/arm/include/asm/fixmap.h @@ -7,14 +7,14 @@ #define FIXADDR_TOP (FIXADDR_END - PAGE_SIZE) #include <linux/pgtable.h> -#include <asm/kmap_types.h> +#include <asm/kmap_size.h> enum fixed_addresses { FIX_EARLYCON_MEM_BASE, __end_of_permanent_fixed_addresses, FIX_KMAP_BEGIN = __end_of_permanent_fixed_addresses, - FIX_KMAP_END = FIX_...

...minus the PMD that + * has been defined in the data section by head_32.S (see + * initial_pg_fixmap). + * Note: This is similar to what early_ioremap_page_table_range_init + * does except that the "end" has PMD_SIZE expunged as per previous + * comment. + */ + fixmap_end_pmd_idx = (FIXADDR_TOP - 1) >> PMD_SHIFT; + btmap_begin_pmd_idx = __fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT; + + size = fixmap_end_pmd_idx - fixmap_begin_pmd_idx; + /* + * early_ioremap_init has already allocated a PMD at + * btmap_begin_pmd_idx + */ + if (btmap_begin_pmd_idx < fixmap_end_pmd_idx) +...

...lude <linux/pagemap.h> #include <linux/spinlock.h> +#include <linux/module.h> #include <asm/system.h> #include <asm/pgtable.h> @@ -138,6 +139,10 @@ void set_pmd_pfn(unsigned long vaddr, un __flush_tlb_one(vaddr); } +static int nr_fixmaps = 0; +unsigned long __FIXADDR_TOP = 0xfffff000; +EXPORT_SYMBOL(__FIXADDR_TOP); + void __set_fixmap (enum fixed_addresses idx, unsigned long phys, pgprot_t flags) { unsigned long address = __fix_to_virt(idx); @@ -147,6 +152,13 @@ void __set_fixmap (enum fixed_addresses return; } set_pte_pfn(address, phys >> PAGE_SH...

...lude <linux/pagemap.h> #include <linux/spinlock.h> +#include <linux/module.h> #include <asm/system.h> #include <asm/pgtable.h> @@ -138,6 +139,10 @@ void set_pmd_pfn(unsigned long vaddr, un __flush_tlb_one(vaddr); } +static int nr_fixmaps = 0; +unsigned long __FIXADDR_TOP = 0xfffff000; +EXPORT_SYMBOL(__FIXADDR_TOP); + void __set_fixmap (enum fixed_addresses idx, unsigned long phys, pgprot_t flags) { unsigned long address = __fix_to_virt(idx); @@ -147,6 +152,13 @@ void __set_fixmap (enum fixed_addresses return; } set_pte_pfn(address, phys >> PAGE_SH...

This is my current set of updates to Xen for 2.6.24. This is largely a bugfix set, and a couple of them are also relevent to 2.6.23. These are in the pre-x86 merge form; I'll update them once the merge goes into git. Quick overview: - remove some dead code in arch/i386/mm/init.c - clean up some duplicate includes - when sending an IPI, yield the vcpu if the destination doesn't have

This is my current set of updates to Xen for 2.6.24. This is largely a bugfix set, and a couple of them are also relevent to 2.6.23. These are in the pre-x86 merge form; I'll update them once the merge goes into git. Quick overview: - remove some dead code in arch/i386/mm/init.c - clean up some duplicate includes - when sending an IPI, yield the vcpu if the destination doesn't have

This is my current set of updates to Xen for 2.6.24. This is largely a bugfix set, and a couple of them are also relevent to 2.6.23. These are in the pre-x86 merge form; I'll update them once the merge goes into git. Quick overview: - remove some dead code in arch/i386/mm/init.c - clean up some duplicate includes - when sending an IPI, yield the vcpu if the destination doesn't have

...: Put .note.* sections into a PT_NOTE segment in vmlinux Cleanups: 1/8: Remove locally-defined ldt structure in favour of standard type 3/8: Allow a kernel to not be in ring 0 5/8: Roll all the cpuid asm into one __cpuid call Hooks: 4/8: Replace sensitive instructions with macros 6/8: Make __FIXADDR_TOP variable to allow it to make space... 7/8: Add a bootparameter to reserve high linear address... 8/8 "Put .note.* sections into a PT_NOTE segment in vmlinux" is mostly here to shake out problems early. It slightly changes the way the vmlinux image is linked together, and it uses the so...

...: Put .note.* sections into a PT_NOTE segment in vmlinux Cleanups: 1/8: Remove locally-defined ldt structure in favour of standard type 3/8: Allow a kernel to not be in ring 0 5/8: Roll all the cpuid asm into one __cpuid call Hooks: 4/8: Replace sensitive instructions with macros 6/8: Make __FIXADDR_TOP variable to allow it to make space... 7/8: Add a bootparameter to reserve high linear address... 8/8 "Put .note.* sections into a PT_NOTE segment in vmlinux" is mostly here to shake out problems early. It slightly changes the way the vmlinux image is linked together, and it uses the so...

Following up to the discussion in: https://lore.kernel.org/r/20200914204209.256266093 at linutronix.de and the second version of this: https://lore.kernel.org/r/20201029221806.189523375 at linutronix.de this series provides a preemptible variant of kmap_atomic & related interfaces. This is achieved by: - Removing the RT dependency from migrate_disable/enable() - Consolidating all

Following up to the discussion in: https://lore.kernel.org/r/20200914204209.256266093 at linutronix.de and the second version of this: https://lore.kernel.org/r/20201029221806.189523375 at linutronix.de this series provides a preemptible variant of kmap_atomic & related interfaces. This is achieved by: - Removing the RT dependency from migrate_disable/enable() - Consolidating all

Following up to the discussion in: https://lore.kernel.org/r/20200914204209.256266093 at linutronix.de and the second version of this: https://lore.kernel.org/r/20201029221806.189523375 at linutronix.de this series provides a preemptible variant of kmap_atomic & related interfaces. This is achieved by: - Removing the RT dependency from migrate_disable/enable() - Consolidating all

...d type 4/13: Allow a kernel to not be in ring 0 6/13: Roll all the cpuid asm into one __cpuid call 9/13: Remove the read hazard from the COW path in copy_one_pte 10/13: Change pte_clear_full to a more appropriately named... Hooks: 5/13: Replace sensitive instructions with macros 7/13: Make __FIXADDR_TOP variable to allow it to make space... 8/13: Add a bootparameter to reserve high linear address... 11/13: Add lazy MMU mode hooks for batching PTE updates 12/13: Pass the mm struct into the pgd_free code so the mm... Probably the most subtle changes here are 11/13 and 9/13, since they add a new...

...d type 4/13: Allow a kernel to not be in ring 0 6/13: Roll all the cpuid asm into one __cpuid call 9/13: Remove the read hazard from the COW path in copy_one_pte 10/13: Change pte_clear_full to a more appropriately named... Hooks: 5/13: Replace sensitive instructions with macros 7/13: Make __FIXADDR_TOP variable to allow it to make space... 8/13: Add a bootparameter to reserve high linear address... 11/13: Add lazy MMU mode hooks for batching PTE updates 12/13: Pass the mm struct into the pgd_free code so the mm... Probably the most subtle changes here are 11/13 and 9/13, since they add a new...