[GIT pull] x86 fixes for 4.4
From: Thomas Gleixner
Date: Sun Nov 22 2015 - 01:39:15 EST
Linus,
please pull the latest x86-urgent-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-urgent-for-linus
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.
Thanks,
tglx
------------------>
Andrew Cooper (1):
x86/cpu: Fix SMAP check in PVOPS environments
Dave Hansen (3):
x86/mpx: Do proper get_user() when running 32-bit binaries on 64-bit kernels
x86/mpx: Fix 32-bit address space calculation
x86/fpu: Fix 32-bit signal frame handling
Huaitong Han (1):
x86/fpu: Fix get_xsave_addr() behavior under virtualization
Namhyung Kim (1):
x86/ftrace: Add comment on static function tracing
arch/x86/kernel/cpu/common.c | 3 +--
arch/x86/kernel/fpu/signal.c | 11 +++++------
arch/x86/kernel/fpu/xstate.c | 1 -
arch/x86/kernel/mcount_64.S | 6 ++++++
arch/x86/mm/mpx.c | 47 ++++++++++++++++++++++++++++++++++++++------
5 files changed, 53 insertions(+), 15 deletions(-)
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 4ddd780aeac9..c2b7522cbf35 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -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)) {
diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c
index ef29b742cea7..31c6a60505e6 100644
--- a/arch/x86/kernel/fpu/signal.c
+++ b/arch/x86/kernel/fpu/signal.c
@@ -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;
}
}
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 6454f2731b56..70fc312221fc 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -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 = ¤t->thread.fpu.state.xsave;
/*
* We should not ever be requesting features that we
* have not enabled. Remember that pcntxt_mask is
diff --git a/arch/x86/kernel/mcount_64.S b/arch/x86/kernel/mcount_64.S
index 94ea120fa21f..87e1762e2bca 100644
--- a/arch/x86/kernel/mcount_64.S
+++ b/arch/x86/kernel/mcount_64.S
@@ -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
diff --git a/arch/x86/mm/mpx.c b/arch/x86/mm/mpx.c
index b0ae85f90f10..1202d5ca2fb5 100644
--- a/arch/x86/mm/mpx.c
+++ b/arch/x86/mm/mpx.c
@@ -586,6 +586,29 @@ static unsigned long mpx_bd_entry_to_bt_addr(struct mm_struct *mm,
}
/*
+ * 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;
}
/*
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/