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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2015-10-19 08:35:30 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2015-10-19 08:35:30 +0300
commitec0a2ed6d8a5e555edef907895c041e285fdb495 (patch)
treea4c8d982f8ac820b1b60818df22ad3ccac2036d5 /kernel/arch/x86/math-emu
parent342fa5dfa053559f47caad657132522496dcf1b3 (diff)
These changes are a raw update to a vanilla kernel 4.1.10, with the
recently announced rt patch patch-4.1.10-rt10.patch. No further changes needed. Change-Id: I9a0cf084498133b10771e744b6da4b29dff706ba Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/arch/x86/math-emu')
-rw-r--r--kernel/arch/x86/math-emu/fpu_entry.c3
-rw-r--r--kernel/arch/x86/math-emu/fpu_system.h21
-rw-r--r--kernel/arch/x86/math-emu/get_address.c3
3 files changed, 20 insertions, 7 deletions
diff --git a/kernel/arch/x86/math-emu/fpu_entry.c b/kernel/arch/x86/math-emu/fpu_entry.c
index 9b8681241..274a52b11 100644
--- a/kernel/arch/x86/math-emu/fpu_entry.c
+++ b/kernel/arch/x86/math-emu/fpu_entry.c
@@ -29,7 +29,6 @@
#include <asm/uaccess.h>
#include <asm/traps.h>
-#include <asm/desc.h>
#include <asm/user.h>
#include <asm/i387.h>
@@ -185,7 +184,7 @@ void math_emulate(struct math_emu_info *info)
math_abort(FPU_info, SIGILL);
}
- code_descriptor = LDT_DESCRIPTOR(FPU_CS);
+ code_descriptor = FPU_get_ldt_descriptor(FPU_CS);
if (SEG_D_SIZE(code_descriptor)) {
/* The above test may be wrong, the book is not clear */
/* Segmented 32 bit protected mode */
diff --git a/kernel/arch/x86/math-emu/fpu_system.h b/kernel/arch/x86/math-emu/fpu_system.h
index 2c614410a..d342fce49 100644
--- a/kernel/arch/x86/math-emu/fpu_system.h
+++ b/kernel/arch/x86/math-emu/fpu_system.h
@@ -16,9 +16,24 @@
#include <linux/kernel.h>
#include <linux/mm.h>
-/* s is always from a cpu register, and the cpu does bounds checking
- * during register load --> no further bounds checks needed */
-#define LDT_DESCRIPTOR(s) (((struct desc_struct *)current->mm->context.ldt)[(s) >> 3])
+#include <asm/desc.h>
+#include <asm/mmu_context.h>
+
+static inline struct desc_struct FPU_get_ldt_descriptor(unsigned seg)
+{
+ static struct desc_struct zero_desc;
+ struct desc_struct ret = zero_desc;
+
+#ifdef CONFIG_MODIFY_LDT_SYSCALL
+ seg >>= 3;
+ mutex_lock(&current->mm->context.lock);
+ if (current->mm->context.ldt && seg < current->mm->context.ldt->size)
+ ret = current->mm->context.ldt->entries[seg];
+ mutex_unlock(&current->mm->context.lock);
+#endif
+ return ret;
+}
+
#define SEG_D_SIZE(x) ((x).b & (3 << 21))
#define SEG_G_BIT(x) ((x).b & (1 << 23))
#define SEG_GRANULARITY(x) (((x).b & (1 << 23)) ? 4096 : 1)
diff --git a/kernel/arch/x86/math-emu/get_address.c b/kernel/arch/x86/math-emu/get_address.c
index 6ef5e9938..8300db71c 100644
--- a/kernel/arch/x86/math-emu/get_address.c
+++ b/kernel/arch/x86/math-emu/get_address.c
@@ -20,7 +20,6 @@
#include <linux/stddef.h>
#include <asm/uaccess.h>
-#include <asm/desc.h>
#include "fpu_system.h"
#include "exception.h"
@@ -158,7 +157,7 @@ static long pm_address(u_char FPU_modrm, u_char segment,
addr->selector = PM_REG_(segment);
}
- descriptor = LDT_DESCRIPTOR(PM_REG_(segment));
+ descriptor = FPU_get_ldt_descriptor(addr->selector);
base_address = SEG_BASE_ADDR(descriptor);
address = base_address + offset;
limit = base_address