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Commit 0f657262 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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:
 "Various x86 low level modifications:

   - preparatory work to support virtually mapped kernel stacks (Andy
     Lutomirski)

   - support for 64-bit __get_user() on 32-bit kernels (Benjamin
     LaHaise)

   - (involved) workaround for Knights Landing CPU erratum (Dave Hansen)

   - MPX enhancements (Dave Hansen)

   - mremap() extension to allow remapping of the special VDSO vma, for
     purposes of user level context save/restore (Dmitry Safonov)

   - hweight and entry code cleanups (Borislav Petkov)

   - bitops code generation optimizations and cleanups with modern GCC
     (H. Peter Anvin)

   - syscall entry code optimizations (Paolo Bonzini)"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (43 commits)
  x86/mm/cpa: Add missing comment in populate_pdg()
  x86/mm/cpa: Fix populate_pgd(): Stop trying to deallocate failed PUDs
  x86/syscalls: Add compat_sys_preadv64v2/compat_sys_pwritev64v2
  x86/smp: Remove unnecessary initialization of thread_info::cpu
  x86/smp: Remove stack_smp_processor_id()
  x86/uaccess: Move thread_info::addr_limit to thread_struct
  x86/dumpstack: Rename thread_struct::sig_on_uaccess_error to sig_on_uaccess_err
  x86/uaccess: Move thread_info::uaccess_err and thread_info::sig_on_uaccess_err to thread_struct
  x86/dumpstack: When OOPSing, rewind the stack before do_exit()
  x86/mm/64: In vmalloc_fault(), use CR3 instead of current->active_mm
  x86/dumpstack/64: Handle faults when printing the "Stack: " part of an OOPS
  x86/dumpstack: Try harder to get a call trace on stack overflow
  x86/mm: Remove kernel_unmap_pages_in_pgd() and efi_cleanup_page_tables()
  x86/mm/cpa: In populate_pgd(), don't set the PGD entry until it's populated
  x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()
  x86/mm: Use pte_none() to test for empty PTE
  x86/mm: Disallow running with 32-bit PTEs to work around erratum
  x86/mm: Ignore A/D bits in pte/pmd/pud_none()
  x86/mm: Move swap offset/type up in PTE to work around erratum
  x86/entry: Inline enter_from_user_mode()
  ...
parents 425dbc6d 55920d31

arch/x86/Kconfig

+0 −5
Original line number Diff line number Diff line
@@ -294,11 +294,6 @@ config X86_32_LAZY_GS 
	def_bool y

	depends on X86_32 && !CC_STACKPROTECTOR



config ARCH_HWEIGHT_CFLAGS

	string

	default "-fcall-saved-ecx -fcall-saved-edx" if X86_32

	default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64



config ARCH_SUPPORTS_UPROBES

	def_bool y

arch/x86/boot/bitops.h

+5 −3
Original line number Diff line number Diff line
@@ -16,14 +16,16 @@ 
#define BOOT_BITOPS_H

#define _LINUX_BITOPS_H		/* Inhibit inclusion of <linux/bitops.h> */



static inline int constant_test_bit(int nr, const void *addr)

#include <linux/types.h>



static inline bool constant_test_bit(int nr, const void *addr)

{

	const u32 *p = (const u32 *)addr;

	return ((1UL << (nr & 31)) & (p[nr >> 5])) != 0;

}

static inline int variable_test_bit(int nr, const void *addr)

static inline bool variable_test_bit(int nr, const void *addr)

{

	u8 v;

	bool v;

	const u32 *p = (const u32 *)addr;



	asm("btl %2,%1; setc %0" : "=qm" (v) : "m" (*p), "Ir" (nr));

arch/x86/boot/boot.h

+10 −8
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ 
#include <linux/types.h>

#include <linux/edd.h>

#include <asm/setup.h>

#include <asm/asm.h>

#include "bitops.h"

#include "ctype.h"

#include "cpuflags.h"
@@ -176,18 +177,18 @@ static inline void wrgs32(u32 v, addr_t addr) 
}



/* Note: these only return true/false, not a signed return value! */

static inline int memcmp_fs(const void *s1, addr_t s2, size_t len)

static inline bool memcmp_fs(const void *s1, addr_t s2, size_t len)

{

	u8 diff;

	asm volatile("fs; repe; cmpsb; setnz %0"

		     : "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));

	bool diff;

	asm volatile("fs; repe; cmpsb" CC_SET(nz)

		     : CC_OUT(nz) (diff), "+D" (s1), "+S" (s2), "+c" (len));

	return diff;

}

static inline int memcmp_gs(const void *s1, addr_t s2, size_t len)

static inline bool memcmp_gs(const void *s1, addr_t s2, size_t len)

{

	u8 diff;

	asm volatile("gs; repe; cmpsb; setnz %0"

		     : "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));

	bool diff;

	asm volatile("gs; repe; cmpsb" CC_SET(nz)

		     : CC_OUT(nz) (diff), "+D" (s1), "+S" (s2), "+c" (len));

	return diff;

}
@@ -294,6 +295,7 @@ static inline int cmdline_find_option_bool(const char *option) 


/* cpu.c, cpucheck.c */

int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);

int check_knl_erratum(void);

int validate_cpu(void);



/* early_serial_console.c */

arch/x86/boot/cpu.c

+2 −0
Original line number Diff line number Diff line
@@ -93,6 +93,8 @@ int validate_cpu(void) 
		show_cap_strs(err_flags);

		putchar('\n');

		return -1;

	} else if (check_knl_erratum()) {

		return -1;

	} else {

		return 0;

	}

arch/x86/boot/cpucheck.c

+33 −0
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ 
# include "boot.h"

#endif

#include <linux/types.h>

#include <asm/intel-family.h>

#include <asm/processor-flags.h>

#include <asm/required-features.h>

#include <asm/msr-index.h>
@@ -175,6 +176,8 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr) 
			puts("WARNING: PAE disabled. Use parameter 'forcepae' to enable at your own risk!\n");

		}

	}

	if (!err)

		err = check_knl_erratum();



	if (err_flags_ptr)

		*err_flags_ptr = err ? err_flags : NULL;
@@ -185,3 +188,33 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr) 


	return (cpu.level < req_level || err) ? -1 : 0;

}



int check_knl_erratum(void)

{

	/*

	 * First check for the affected model/family:

	 */

	if (!is_intel() ||

	    cpu.family != 6 ||

	    cpu.model != INTEL_FAM6_XEON_PHI_KNL)

		return 0;



	/*

	 * This erratum affects the Accessed/Dirty bits, and can

	 * cause stray bits to be set in !Present PTEs.  We have

	 * enough bits in our 64-bit PTEs (which we have on real

	 * 64-bit mode or PAE) to avoid using these troublesome

	 * bits.  But, we do not have enough space in our 32-bit

	 * PTEs.  So, refuse to run on 32-bit non-PAE kernels.

	 */

	if (IS_ENABLED(CONFIG_X86_64) || IS_ENABLED(CONFIG_X86_PAE))

		return 0;



	puts("This 32-bit kernel can not run on this Xeon Phi x200\n"

	     "processor due to a processor erratum.  Use a 64-bit\n"

	     "kernel, or enable PAE in this 32-bit kernel.\n\n");



	return -1;

}