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torvaldstorvalds
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Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar: "A laundry list of changes: KASAN improvements/fixes for ptdump, a self-test fix, PAT cleanup and wbinvd() avoidance, removal of stale code and documentation updates" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm/ptdump: Add address marker for KASAN shadow region x86/mm/ptdump: Optimize check for W+X mappings for CONFIG_KASAN=y x86/mm/pat: Use rb_entry() x86/mpx: Re-add MPX to selftests Makefile x86/mm: Remove CONFIG_DEBUG_NX_TEST x86/mm/cpa: Avoid wbinvd() for PREEMPT x86/mm: Improve documentation for low-level device I/O functions
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‎arch/x86/Kconfig.debug

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Original file line numberDiff line numberDiff line change
@@ -120,14 +120,6 @@ config DEBUG_SET_MODULE_RONX
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against certain classes of kernel exploits.
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If in doubt, say "N".
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config DEBUG_NX_TEST
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tristate "Testcase for the NX non-executable stack feature"
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depends on DEBUG_KERNEL && m
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---help---
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This option enables a testcase for the CPU NX capability
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and the software setup of this feature.
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If in doubt, say "N"
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config DOUBLEFAULT
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default y
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bool "Enable doublefault exception handler" if EXPERT

‎arch/x86/include/asm/io.h

Lines changed: 35 additions & 11 deletions
Original file line numberDiff line numberDiff line change
@@ -164,6 +164,17 @@ static inline unsigned int isa_virt_to_bus(volatile void *address)
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#define virt_to_bus virt_to_phys
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#define bus_to_virt phys_to_virt
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167+
/*
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* The default ioremap() behavior is non-cached; if you need something
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* else, you probably want one of the following.
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*/
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extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
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extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
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#define ioremap_uc ioremap_uc
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extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
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extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, unsigned long prot_val);
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/**
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* ioremap - map bus memory into CPU space
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* @offset: bus address of the memory
@@ -178,17 +189,6 @@ static inline unsigned int isa_virt_to_bus(volatile void *address)
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* If the area you are trying to map is a PCI BAR you should have a
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* look at pci_iomap().
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*/
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extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
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extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
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#define ioremap_uc ioremap_uc
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extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
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extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size,
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unsigned long prot_val);
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/*
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* The default ioremap() behavior is non-cached:
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*/
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static inline void __iomem *ioremap(resource_size_t offset, unsigned long size)
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{
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return ioremap_nocache(offset, size);
@@ -207,18 +207,42 @@ extern void set_iounmap_nonlazy(void);
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*/
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#define xlate_dev_kmem_ptr(p) p
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210+
/**
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* memset_io Set a range of I/O memory to a constant value
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* @addr: The beginning of the I/O-memory range to set
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* @val: The value to set the memory to
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* @count: The number of bytes to set
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*
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* Set a range of I/O memory to a given value.
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*/
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static inline void
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memset_io(volatile void __iomem *addr, unsigned char val, size_t count)
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{
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memset((void __force *)addr, val, count);
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}
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224+
/**
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* memcpy_fromio Copy a block of data from I/O memory
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* @dst: The (RAM) destination for the copy
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* @src: The (I/O memory) source for the data
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* @count: The number of bytes to copy
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*
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* Copy a block of data from I/O memory.
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*/
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static inline void
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memcpy_fromio(void *dst, const volatile void __iomem *src, size_t count)
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{
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memcpy(dst, (const void __force *)src, count);
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}
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/**
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* memcpy_toio Copy a block of data into I/O memory
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* @dst: The (I/O memory) destination for the copy
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* @src: The (RAM) source for the data
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* @count: The number of bytes to copy
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*
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* Copy a block of data to I/O memory.
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*/
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static inline void
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memcpy_toio(volatile void __iomem *dst, const void *src, size_t count)
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{

‎arch/x86/kernel/Makefile

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Original file line numberDiff line numberDiff line change
@@ -101,7 +101,6 @@ obj-$(CONFIG_APB_TIMER) += apb_timer.o
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102102
obj-$(CONFIG_AMD_NB) += amd_nb.o
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obj-$(CONFIG_DEBUG_RODATA_TEST) += test_rodata.o
104-
obj-$(CONFIG_DEBUG_NX_TEST) += test_nx.o
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obj-$(CONFIG_DEBUG_NMI_SELFTEST) += nmi_selftest.o
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obj-$(CONFIG_KVM_GUEST) += kvm.o kvmclock.o

‎arch/x86/kernel/test_nx.c

Lines changed: 0 additions & 173 deletions
This file was deleted.

‎arch/x86/mm/dump_pagetables.c

Lines changed: 24 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -18,6 +18,7 @@
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#include <linux/sched.h>
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#include <linux/seq_file.h>
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#include <asm/kasan.h>
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#include <asm/pgtable.h>
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/*
@@ -51,6 +52,10 @@ enum address_markers_idx {
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LOW_KERNEL_NR,
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VMALLOC_START_NR,
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VMEMMAP_START_NR,
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#ifdef CONFIG_KASAN
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KASAN_SHADOW_START_NR,
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KASAN_SHADOW_END_NR,
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#endif
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# ifdef CONFIG_X86_ESPFIX64
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ESPFIX_START_NR,
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# endif
@@ -76,6 +81,10 @@ static struct addr_marker address_markers[] = {
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{ 0/* PAGE_OFFSET */, "Low Kernel Mapping" },
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{ 0/* VMALLOC_START */, "vmalloc() Area" },
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{ 0/* VMEMMAP_START */, "Vmemmap" },
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#ifdef CONFIG_KASAN
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{ KASAN_SHADOW_START, "KASAN shadow" },
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{ KASAN_SHADOW_END, "KASAN shadow end" },
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#endif
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# ifdef CONFIG_X86_ESPFIX64
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{ ESPFIX_BASE_ADDR, "ESPfix Area", 16 },
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# endif
@@ -327,18 +336,31 @@ static void walk_pmd_level(struct seq_file *m, struct pg_state *st, pud_t addr,
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328337
#if PTRS_PER_PUD > 1
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/*
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* This is an optimization for CONFIG_DEBUG_WX=y + CONFIG_KASAN=y
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* KASAN fills page tables with the same values. Since there is no
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* point in checking page table more than once we just skip repeated
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* entries. This saves us dozens of seconds during boot.
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*/
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static bool pud_already_checked(pud_t *prev_pud, pud_t *pud, bool checkwx)
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{
347+
return checkwx && prev_pud && (pud_val(*prev_pud) == pud_val(*pud));
348+
}
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static void walk_pud_level(struct seq_file *m, struct pg_state *st, pgd_t addr,
331351
unsigned long P)
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{
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int i;
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pud_t *start;
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pgprotval_t prot;
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pud_t *prev_pud = NULL;
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337358
start = (pud_t *) pgd_page_vaddr(addr);
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for (i = 0; i < PTRS_PER_PUD; i++) {
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st->current_address = normalize_addr(P + i * PUD_LEVEL_MULT);
341-
if (!pud_none(*start)) {
362+
if (!pud_none(*start) &&
363+
!pud_already_checked(prev_pud, start, st->check_wx)) {
342364
if (pud_large(*start) || !pud_present(*start)) {
343365
prot = pud_flags(*start);
344366
note_page(m, st, __pgprot(prot), 2);
@@ -349,6 +371,7 @@ static void walk_pud_level(struct seq_file *m, struct pg_state *st, pgd_t addr,
349371
} else
350372
note_page(m, st, __pgprot(0), 2);
351373

374+
prev_pud = start;
352375
start++;
353376
}
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}

‎arch/x86/mm/pageattr.c

Lines changed: 13 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -214,7 +214,20 @@ static void cpa_flush_array(unsigned long *start, int numpages, int cache,
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int in_flags, struct page **pages)
215215
{
216216
unsigned int i, level;
217+
#ifdef CONFIG_PREEMPT
218+
/*
219+
* Avoid wbinvd() because it causes latencies on all CPUs,
220+
* regardless of any CPU isolation that may be in effect.
221+
*
222+
* This should be extended for CAT enabled systems independent of
223+
* PREEMPT because wbinvd() does not respect the CAT partitions and
224+
* this is exposed to unpriviledged users through the graphics
225+
* subsystem.
226+
*/
227+
unsigned long do_wbinvd = 0;
228+
#else
217229
unsigned long do_wbinvd = cache && numpages >= 1024; /* 4M threshold */
230+
#endif
218231

219232
BUG_ON(irqs_disabled());
220233

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