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authorLinus Torvalds2018-10-23 13:08:53 +0100
committerLinus Torvalds2018-10-23 13:08:53 +0100
commit0200fbdd431519d730b5d399a12840ec832b27cc (patch)
tree2b58f9e24b61b00e0550f106c95bfabc3b52cfdd /arch/s390
parentde3fbb2aa802a267dee2213ae7d5a1e19eb4294a (diff)
parent01a14bda11add9dcd4a59200f13834d634559935 (diff)
Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking and misc x86 updates from Ingo Molnar: "Lots of changes in this cycle - in part because locking/core attracted a number of related x86 low level work which was easier to handle in a single tree: - Linux Kernel Memory Consistency Model updates (Alan Stern, Paul E. McKenney, Andrea Parri) - lockdep scalability improvements and micro-optimizations (Waiman Long) - rwsem improvements (Waiman Long) - spinlock micro-optimization (Matthew Wilcox) - qspinlocks: Provide a liveness guarantee (more fairness) on x86. (Peter Zijlstra) - Add support for relative references in jump tables on arm64, x86 and s390 to optimize jump labels (Ard Biesheuvel, Heiko Carstens) - Be a lot less permissive on weird (kernel address) uaccess faults on x86: BUG() when uaccess helpers fault on kernel addresses (Jann Horn) - macrofy x86 asm statements to un-confuse the GCC inliner. (Nadav Amit) - ... and a handful of other smaller changes as well" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits) locking/lockdep: Make global debug_locks* variables read-mostly locking/lockdep: Fix debug_locks off performance problem locking/pvqspinlock: Extend node size when pvqspinlock is configured locking/qspinlock_stat: Count instances of nested lock slowpaths locking/qspinlock, x86: Provide liveness guarantee x86/asm: 'Simplify' GEN_*_RMWcc() macros locking/qspinlock: Rework some comments locking/qspinlock: Re-order code locking/lockdep: Remove duplicated 'lock_class_ops' percpu array x86/defconfig: Enable CONFIG_USB_XHCI_HCD=y futex: Replace spin_is_locked() with lockdep locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs x86/extable: Macrofy inline assembly code to work around GCC inlining bugs x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs x86/refcount: Work around GCC inlining bug x86/objtool: Use asm macros to work around GCC inlining bugs ...
Diffstat (limited to 'arch/s390')
-rw-r--r--arch/s390/Kconfig1
-rw-r--r--arch/s390/include/asm/jump_label.h40
-rw-r--r--arch/s390/kernel/jump_label.c11
-rw-r--r--arch/s390/kernel/vmlinux.lds.S1
4 files changed, 24 insertions, 29 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index cc8313550493..039a3417dfc4 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -126,6 +126,7 @@ config S390
select HAVE_ALIGNED_STRUCT_PAGE if SLUB
select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_JUMP_LABEL
+ select HAVE_ARCH_JUMP_LABEL_RELATIVE
select HAVE_ARCH_KASAN
select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES
select HAVE_ARCH_SECCOMP_FILTER
diff --git a/arch/s390/include/asm/jump_label.h b/arch/s390/include/asm/jump_label.h
index 40f651292aa7..e2d3e6c43395 100644
--- a/arch/s390/include/asm/jump_label.h
+++ b/arch/s390/include/asm/jump_label.h
@@ -14,41 +14,33 @@
* We use a brcl 0,2 instruction for jump labels at compile time so it
* can be easily distinguished from a hotpatch generated instruction.
*/
-static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
+static inline bool arch_static_branch(struct static_key *key, bool branch)
{
- asm_volatile_goto("0: brcl 0,"__stringify(JUMP_LABEL_NOP_OFFSET)"\n"
- ".pushsection __jump_table, \"aw\"\n"
- ".balign 8\n"
- ".quad 0b, %l[label], %0\n"
- ".popsection\n"
- : : "X" (&((char *)key)[branch]) : : label);
-
+ asm_volatile_goto("0: brcl 0,"__stringify(JUMP_LABEL_NOP_OFFSET)"\n"
+ ".pushsection __jump_table,\"aw\"\n"
+ ".balign 8\n"
+ ".long 0b-.,%l[label]-.\n"
+ ".quad %0-.\n"
+ ".popsection\n"
+ : : "X" (&((char *)key)[branch]) : : label);
return false;
label:
return true;
}
-static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
+static inline bool arch_static_branch_jump(struct static_key *key, bool branch)
{
- asm_volatile_goto("0: brcl 15, %l[label]\n"
- ".pushsection __jump_table, \"aw\"\n"
- ".balign 8\n"
- ".quad 0b, %l[label], %0\n"
- ".popsection\n"
- : : "X" (&((char *)key)[branch]) : : label);
-
+ asm_volatile_goto("0: brcl 15,%l[label]\n"
+ ".pushsection __jump_table,\"aw\"\n"
+ ".balign 8\n"
+ ".long 0b-.,%l[label]-.\n"
+ ".quad %0-.\n"
+ ".popsection\n"
+ : : "X" (&((char *)key)[branch]) : : label);
return false;
label:
return true;
}
-typedef unsigned long jump_label_t;
-
-struct jump_entry {
- jump_label_t code;
- jump_label_t target;
- jump_label_t key;
-};
-
#endif /* __ASSEMBLY__ */
#endif
diff --git a/arch/s390/kernel/jump_label.c b/arch/s390/kernel/jump_label.c
index 43f8430fb67d..50a1798604a8 100644
--- a/arch/s390/kernel/jump_label.c
+++ b/arch/s390/kernel/jump_label.c
@@ -33,13 +33,13 @@ static void jump_label_make_branch(struct jump_entry *entry, struct insn *insn)
{
/* brcl 15,offset */
insn->opcode = 0xc0f4;
- insn->offset = (entry->target - entry->code) >> 1;
+ insn->offset = (jump_entry_target(entry) - jump_entry_code(entry)) >> 1;
}
static void jump_label_bug(struct jump_entry *entry, struct insn *expected,
struct insn *new)
{
- unsigned char *ipc = (unsigned char *)entry->code;
+ unsigned char *ipc = (unsigned char *)jump_entry_code(entry);
unsigned char *ipe = (unsigned char *)expected;
unsigned char *ipn = (unsigned char *)new;
@@ -59,6 +59,7 @@ static void __jump_label_transform(struct jump_entry *entry,
enum jump_label_type type,
int init)
{
+ void *code = (void *)jump_entry_code(entry);
struct insn old, new;
if (type == JUMP_LABEL_JMP) {
@@ -69,13 +70,13 @@ static void __jump_label_transform(struct jump_entry *entry,
jump_label_make_nop(entry, &new);
}
if (init) {
- if (memcmp((void *)entry->code, &orignop, sizeof(orignop)))
+ if (memcmp(code, &orignop, sizeof(orignop)))
jump_label_bug(entry, &orignop, &new);
} else {
- if (memcmp((void *)entry->code, &old, sizeof(old)))
+ if (memcmp(code, &old, sizeof(old)))
jump_label_bug(entry, &old, &new);
}
- s390_kernel_write((void *)entry->code, &new, sizeof(new));
+ s390_kernel_write(code, &new, sizeof(new));
}
static int __sm_arch_jump_label_transform(void *data)
diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S
index cc3cbdc93d35..21eb7407d51b 100644
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -65,6 +65,7 @@ SECTIONS
__start_ro_after_init = .;
.data..ro_after_init : {
*(.data..ro_after_init)
+ JUMP_TABLE_DATA
}
EXCEPTION_TABLE(16)
. = ALIGN(PAGE_SIZE);