Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "This update contains:

   - MPX updates for handling 32bit processes

   - A fix for a long standing bug in 32bit signal frame handling
     related to FPU/XSAVE state

   - Handle get_xsave_addr() correctly in KVM

   - Fix SMAP check under paravirtualization

   - Add a comment to the static function trace entry to avoid further
     confusion about the difference to dynamic tracing"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu: Fix SMAP check in PVOPS environments
  x86/ftrace: Add comment on static function tracing
  x86/fpu: Fix get_xsave_addr() behavior under virtualization
  x86/fpu: Fix 32-bit signal frame handling
  x86/mpx: Fix 32-bit address space calculation
  x86/mpx: Do proper get_user() when running 32-bit binaries on 64-bit kernels
This commit is contained in:
Linus Torvalds 2015-11-22 12:00:12 -08:00
commit 069ec22915
5 changed files with 53 additions and 15 deletions

View File

@ -273,10 +273,9 @@ __setup("nosmap", setup_disable_smap);
static __always_inline void setup_smap(struct cpuinfo_x86 *c)
{
unsigned long eflags;
unsigned long eflags = native_save_fl();
/* This should have been cleared long ago */
raw_local_save_flags(eflags);
BUG_ON(eflags & X86_EFLAGS_AC);
if (cpu_has(c, X86_FEATURE_SMAP)) {

View File

@ -385,20 +385,19 @@ fpu__alloc_mathframe(unsigned long sp, int ia32_frame,
*/
void fpu__init_prepare_fx_sw_frame(void)
{
int fsave_header_size = sizeof(struct fregs_state);
int size = xstate_size + FP_XSTATE_MAGIC2_SIZE;
if (config_enabled(CONFIG_X86_32))
size += fsave_header_size;
fx_sw_reserved.magic1 = FP_XSTATE_MAGIC1;
fx_sw_reserved.extended_size = size;
fx_sw_reserved.xfeatures = xfeatures_mask;
fx_sw_reserved.xstate_size = xstate_size;
if (config_enabled(CONFIG_IA32_EMULATION)) {
if (config_enabled(CONFIG_IA32_EMULATION) ||
config_enabled(CONFIG_X86_32)) {
int fsave_header_size = sizeof(struct fregs_state);
fx_sw_reserved_ia32 = fx_sw_reserved;
fx_sw_reserved_ia32.extended_size += fsave_header_size;
fx_sw_reserved_ia32.extended_size = size + fsave_header_size;
}
}

View File

@ -694,7 +694,6 @@ void *get_xsave_addr(struct xregs_state *xsave, int xstate_feature)
if (!boot_cpu_has(X86_FEATURE_XSAVE))
return NULL;
xsave = &current->thread.fpu.state.xsave;
/*
* We should not ever be requesting features that we
* have not enabled. Remember that pcntxt_mask is

View File

@ -278,6 +278,12 @@ trace:
/* save_mcount_regs fills in first two parameters */
save_mcount_regs
/*
* When DYNAMIC_FTRACE is not defined, ARCH_SUPPORTS_FTRACE_OPS is not
* set (see include/asm/ftrace.h and include/linux/ftrace.h). Only the
* ip and parent ip are used and the list function is called when
* function tracing is enabled.
*/
call *ftrace_trace_function
restore_mcount_regs

View File

@ -585,6 +585,29 @@ static unsigned long mpx_bd_entry_to_bt_addr(struct mm_struct *mm,
return bt_addr;
}
/*
* We only want to do a 4-byte get_user() on 32-bit. Otherwise,
* we might run off the end of the bounds table if we are on
* a 64-bit kernel and try to get 8 bytes.
*/
int get_user_bd_entry(struct mm_struct *mm, unsigned long *bd_entry_ret,
long __user *bd_entry_ptr)
{
u32 bd_entry_32;
int ret;
if (is_64bit_mm(mm))
return get_user(*bd_entry_ret, bd_entry_ptr);
/*
* Note that get_user() uses the type of the *pointer* to
* establish the size of the get, not the destination.
*/
ret = get_user(bd_entry_32, (u32 __user *)bd_entry_ptr);
*bd_entry_ret = bd_entry_32;
return ret;
}
/*
* Get the base of bounds tables pointed by specific bounds
* directory entry.
@ -605,7 +628,7 @@ static int get_bt_addr(struct mm_struct *mm,
int need_write = 0;
pagefault_disable();
ret = get_user(bd_entry, bd_entry_ptr);
ret = get_user_bd_entry(mm, &bd_entry, bd_entry_ptr);
pagefault_enable();
if (!ret)
break;
@ -700,11 +723,23 @@ static unsigned long mpx_get_bt_entry_offset_bytes(struct mm_struct *mm,
*/
static inline unsigned long bd_entry_virt_space(struct mm_struct *mm)
{
unsigned long long virt_space = (1ULL << boot_cpu_data.x86_virt_bits);
if (is_64bit_mm(mm))
return virt_space / MPX_BD_NR_ENTRIES_64;
else
return virt_space / MPX_BD_NR_ENTRIES_32;
unsigned long long virt_space;
unsigned long long GB = (1ULL << 30);
/*
* This covers 32-bit emulation as well as 32-bit kernels
* running on 64-bit harware.
*/
if (!is_64bit_mm(mm))
return (4ULL * GB) / MPX_BD_NR_ENTRIES_32;
/*
* 'x86_virt_bits' returns what the hardware is capable
* of, and returns the full >32-bit adddress space when
* running 32-bit kernels on 64-bit hardware.
*/
virt_space = (1ULL << boot_cpu_data.x86_virt_bits);
return virt_space / MPX_BD_NR_ENTRIES_64;
}
/*