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-rw-r--r--arch/sh/kernel/Makefile1
-rw-r--r--arch/sh/kernel/process.c2
-rw-r--r--arch/sh/kernel/signal.c17
-rw-r--r--arch/sh/kernel/vsyscall/Makefile36
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall-note.S25
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall-sigreturn.S39
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall-syscall.S10
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall-trapa.S42
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall.c150
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall.lds.S74
-rw-r--r--arch/sh/mm/Kconfig13
-rw-r--r--arch/sh/mm/init.c3
-rw-r--r--arch/sh/mm/tlb-flush.c18
13 files changed, 418 insertions, 12 deletions
diff --git a/arch/sh/kernel/Makefile b/arch/sh/kernel/Makefile
index 0e2148f63e7..5da88a43d35 100644
--- a/arch/sh/kernel/Makefile
+++ b/arch/sh/kernel/Makefile
@@ -9,6 +9,7 @@ obj-y := process.o signal.o entry.o traps.o irq.o \
io.o io_generic.o sh_ksyms.o syscalls.o
obj-y += cpu/ timers/
+obj-$(CONFIG_VSYSCALL) += vsyscall/
obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_CF_ENABLER) += cf-enabler.o
diff --git a/arch/sh/kernel/process.c b/arch/sh/kernel/process.c
index 630ec1af248..0b1d5dd7a93 100644
--- a/arch/sh/kernel/process.c
+++ b/arch/sh/kernel/process.c
@@ -355,7 +355,7 @@ struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *ne
else if (next->thread.ubc_pc && next->mm) {
int asid = 0;
#ifdef CONFIG_MMU
- asid |= next->mm->context & MMU_CONTEXT_ASID_MASK;
+ asid |= next->mm->context.id & MMU_CONTEXT_ASID_MASK;
#endif
ubc_set_tracing(asid, next->thread.ubc_pc);
} else {
diff --git a/arch/sh/kernel/signal.c b/arch/sh/kernel/signal.c
index 2f1c9545b49..5213f5bc6ce 100644
--- a/arch/sh/kernel/signal.c
+++ b/arch/sh/kernel/signal.c
@@ -8,7 +8,6 @@
* SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
*
*/
-
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
@@ -21,6 +20,7 @@
#include <linux/unistd.h>
#include <linux/stddef.h>
#include <linux/tty.h>
+#include <linux/elf.h>
#include <linux/personality.h>
#include <linux/binfmts.h>
@@ -29,8 +29,6 @@
#include <asm/pgtable.h>
#include <asm/cacheflush.h>
-#undef DEBUG
-
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
/*
@@ -312,6 +310,11 @@ get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
return (void __user *)((sp - frame_size) & -8ul);
}
+/* These symbols are defined with the addresses in the vsyscall page.
+ See vsyscall-trapa.S. */
+extern void __user __kernel_sigreturn;
+extern void __user __kernel_rt_sigreturn;
+
static int setup_frame(int sig, struct k_sigaction *ka,
sigset_t *set, struct pt_regs *regs)
{
@@ -340,6 +343,10 @@ static int setup_frame(int sig, struct k_sigaction *ka,
already in userspace. */
if (ka->sa.sa_flags & SA_RESTORER) {
regs->pr = (unsigned long) ka->sa.sa_restorer;
+#ifdef CONFIG_VSYSCALL
+ } else if (likely(current->mm->context.vdso)) {
+ regs->pr = VDSO_SYM(&__kernel_sigreturn);
+#endif
} else {
/* Generate return code (system call to sigreturn) */
err |= __put_user(MOVW(7), &frame->retcode[0]);
@@ -416,6 +423,10 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
already in userspace. */
if (ka->sa.sa_flags & SA_RESTORER) {
regs->pr = (unsigned long) ka->sa.sa_restorer;
+#ifdef CONFIG_VSYSCALL
+ } else if (likely(current->mm->context.vdso)) {
+ regs->pr = VDSO_SYM(&__kernel_rt_sigreturn);
+#endif
} else {
/* Generate return code (system call to rt_sigreturn) */
err |= __put_user(MOVW(7), &frame->retcode[0]);
diff --git a/arch/sh/kernel/vsyscall/Makefile b/arch/sh/kernel/vsyscall/Makefile
new file mode 100644
index 00000000000..4bbce1cfa35
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/Makefile
@@ -0,0 +1,36 @@
+obj-y += vsyscall.o vsyscall-syscall.o
+
+$(obj)/vsyscall-syscall.o: \
+ $(foreach F,trapa,$(obj)/vsyscall-$F.so)
+
+# Teach kbuild about targets
+targets += $(foreach F,trapa,vsyscall-$F.o vsyscall-$F.so)
+targets += vsyscall-note.o vsyscall.lds
+
+# The DSO images are built using a special linker script
+quiet_cmd_syscall = SYSCALL $@
+ cmd_syscall = $(CC) -nostdlib $(SYSCFLAGS_$(@F)) \
+ -Wl,-T,$(filter-out FORCE,$^) -o $@
+
+export CPPFLAGS_vsyscall.lds += -P -C -Ush
+
+vsyscall-flags = -shared -s -Wl,-soname=linux-gate.so.1 \
+ $(call ld-option, -Wl$(comma)--hash-style=sysv)
+
+SYSCFLAGS_vsyscall-trapa.so = $(vsyscall-flags)
+
+$(obj)/vsyscall-trapa.so: \
+$(obj)/vsyscall-%.so: $(src)/vsyscall.lds $(obj)/vsyscall-%.o FORCE
+ $(call if_changed,syscall)
+
+# We also create a special relocatable object that should mirror the symbol
+# table and layout of the linked DSO. With ld -R we can then refer to
+# these symbols in the kernel code rather than hand-coded addresses.
+extra-y += vsyscall-syms.o
+$(obj)/built-in.o: $(obj)/vsyscall-syms.o
+$(obj)/built-in.o: ld_flags += -R $(obj)/vsyscall-syms.o
+
+SYSCFLAGS_vsyscall-syms.o = -r
+$(obj)/vsyscall-syms.o: $(src)/vsyscall.lds \
+ $(obj)/vsyscall-trapa.o $(obj)/vsyscall-note.o FORCE
+ $(call if_changed,syscall)
diff --git a/arch/sh/kernel/vsyscall/vsyscall-note.S b/arch/sh/kernel/vsyscall/vsyscall-note.S
new file mode 100644
index 00000000000..d4b5be4f3d5
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall-note.S
@@ -0,0 +1,25 @@
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+
+#define ASM_ELF_NOTE_BEGIN(name, flags, vendor, type) \
+ .section name, flags; \
+ .balign 4; \
+ .long 1f - 0f; /* name length */ \
+ .long 3f - 2f; /* data length */ \
+ .long type; /* note type */ \
+0: .asciz vendor; /* vendor name */ \
+1: .balign 4; \
+2:
+
+#define ASM_ELF_NOTE_END \
+3: .balign 4; /* pad out section */ \
+ .previous
+
+ ASM_ELF_NOTE_BEGIN(".note.kernel-version", "a", UTS_SYSNAME, 0)
+ .long LINUX_VERSION_CODE
+ ASM_ELF_NOTE_END
diff --git a/arch/sh/kernel/vsyscall/vsyscall-sigreturn.S b/arch/sh/kernel/vsyscall/vsyscall-sigreturn.S
new file mode 100644
index 00000000000..555a64f124c
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall-sigreturn.S
@@ -0,0 +1,39 @@
+#include <asm/unistd.h>
+
+ .text
+ .balign 32
+ .globl __kernel_sigreturn
+ .type __kernel_sigreturn,@function
+__kernel_sigreturn:
+.LSTART_sigreturn:
+ mov.w 1f, r3
+ trapa #0x10
+ or r0, r0
+ or r0, r0
+ or r0, r0
+ or r0, r0
+ or r0, r0
+
+1: .short __NR_sigreturn
+.LEND_sigreturn:
+ .size __kernel_sigreturn,.-.LSTART_sigreturn
+
+ .balign 32
+ .globl __kernel_rt_sigreturn
+ .type __kernel_rt_sigreturn,@function
+__kernel_rt_sigreturn:
+.LSTART_rt_sigreturn:
+ mov.w 1f, r3
+ trapa #0x10
+ or r0, r0
+ or r0, r0
+ or r0, r0
+ or r0, r0
+ or r0, r0
+
+1: .short __NR_rt_sigreturn
+.LEND_rt_sigreturn:
+ .size __kernel_rt_sigreturn,.-.LSTART_rt_sigreturn
+
+ .section .eh_frame,"a",@progbits
+ .previous
diff --git a/arch/sh/kernel/vsyscall/vsyscall-syscall.S b/arch/sh/kernel/vsyscall/vsyscall-syscall.S
new file mode 100644
index 00000000000..c2ac7f0282b
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall-syscall.S
@@ -0,0 +1,10 @@
+#include <linux/init.h>
+
+__INITDATA
+
+ .globl vsyscall_trapa_start, vsyscall_trapa_end
+vsyscall_trapa_start:
+ .incbin "arch/sh/kernel/vsyscall/vsyscall-trapa.so"
+vsyscall_trapa_end:
+
+__FINIT
diff --git a/arch/sh/kernel/vsyscall/vsyscall-trapa.S b/arch/sh/kernel/vsyscall/vsyscall-trapa.S
new file mode 100644
index 00000000000..3b6eb34c43f
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall-trapa.S
@@ -0,0 +1,42 @@
+ .text
+ .globl __kernel_vsyscall
+ .type __kernel_vsyscall,@function
+__kernel_vsyscall:
+.LSTART_vsyscall:
+ /* XXX: We'll have to do something here once we opt to use the vDSO
+ * page for something other than the signal trampoline.. as well as
+ * fill out .eh_frame -- PFM. */
+.LEND_vsyscall:
+ .size __kernel_vsyscall,.-.LSTART_vsyscall
+ .previous
+
+ .section .eh_frame,"a",@progbits
+.LCIE:
+ .ualong .LCIE_end - .LCIE_start
+.LCIE_start:
+ .ualong 0 /* CIE ID */
+ .byte 0x1 /* Version number */
+ .string "zRS" /* NUL-terminated augmentation string */
+ .uleb128 0x1 /* Code alignment factor */
+ .sleb128 -4 /* Data alignment factor */
+ .byte 0x11 /* Return address register column */
+ /* Augmentation length and data (none) */
+ .byte 0xc /* DW_CFA_def_cfa */
+ .uleb128 0xf /* r15 */
+ .uleb128 0x0 /* offset 0 */
+
+ .align 2
+.LCIE_end:
+
+ .ualong .LFDE_end-.LFDE_start /* Length FDE */
+.LFDE_start:
+ .ualong .LCIE /* CIE pointer */
+ .ualong .LSTART_vsyscall-. /* start address */
+ .ualong .LEND_vsyscall-.LSTART_vsyscall
+ .uleb128 0
+ .align 2
+.LFDE_end:
+ .previous
+
+/* Get the common code for the sigreturn entry points */
+#include "vsyscall-sigreturn.S"
diff --git a/arch/sh/kernel/vsyscall/vsyscall.c b/arch/sh/kernel/vsyscall/vsyscall.c
new file mode 100644
index 00000000000..075d6cc1a2d
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall.c
@@ -0,0 +1,150 @@
+/*
+ * arch/sh/kernel/vsyscall.c
+ *
+ * Copyright (C) 2006 Paul Mundt
+ *
+ * vDSO randomization
+ * Copyright(C) 2005-2006, Red Hat, Inc., Ingo Molnar
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/gfp.h>
+#include <linux/module.h>
+#include <linux/elf.h>
+
+/*
+ * Should the kernel map a VDSO page into processes and pass its
+ * address down to glibc upon exec()?
+ */
+unsigned int __read_mostly vdso_enabled = 1;
+EXPORT_SYMBOL_GPL(vdso_enabled);
+
+static int __init vdso_setup(char *s)
+{
+ vdso_enabled = simple_strtoul(s, NULL, 0);
+ return 1;
+}
+__setup("vdso=", vdso_setup);
+
+/*
+ * These symbols are defined by vsyscall.o to mark the bounds
+ * of the ELF DSO images included therein.
+ */
+extern const char vsyscall_trapa_start, vsyscall_trapa_end;
+static void *syscall_page;
+
+int __init vsyscall_init(void)
+{
+ syscall_page = (void *)get_zeroed_page(GFP_ATOMIC);
+
+ /*
+ * XXX: Map this page to a fixmap entry if we get around
+ * to adding the page to ELF core dumps
+ */
+
+ memcpy(syscall_page,
+ &vsyscall_trapa_start,
+ &vsyscall_trapa_end - &vsyscall_trapa_start);
+
+ return 0;
+}
+
+static struct page *syscall_vma_nopage(struct vm_area_struct *vma,
+ unsigned long address, int *type)
+{
+ unsigned long offset = address - vma->vm_start;
+ struct page *page;
+
+ if (address < vma->vm_start || address > vma->vm_end)
+ return NOPAGE_SIGBUS;
+
+ page = virt_to_page(syscall_page + offset);
+
+ get_page(page);
+
+ return page;
+}
+
+/* Prevent VMA merging */
+static void syscall_vma_close(struct vm_area_struct *vma)
+{
+}
+
+static struct vm_operations_struct syscall_vm_ops = {
+ .nopage = syscall_vma_nopage,
+ .close = syscall_vma_close,
+};
+
+/* Setup a VMA at program startup for the vsyscall page */
+int arch_setup_additional_pages(struct linux_binprm *bprm,
+ int executable_stack)
+{
+ struct vm_area_struct *vma;
+ struct mm_struct *mm = current->mm;
+ unsigned long addr;
+ int ret;
+
+ down_write(&mm->mmap_sem);
+ addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0);
+ if (IS_ERR_VALUE(addr)) {
+ ret = addr;
+ goto up_fail;
+ }
+
+ vma = kmem_cache_zalloc(vm_area_cachep, SLAB_KERNEL);
+ if (!vma) {
+ ret = -ENOMEM;
+ goto up_fail;
+ }
+
+ vma->vm_start = addr;
+ vma->vm_end = addr + PAGE_SIZE;
+ /* MAYWRITE to allow gdb to COW and set breakpoints */
+ vma->vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYEXEC|VM_MAYWRITE;
+ vma->vm_flags |= mm->def_flags;
+ vma->vm_page_prot = protection_map[vma->vm_flags & 7];
+ vma->vm_ops = &syscall_vm_ops;
+ vma->vm_mm = mm;
+
+ ret = insert_vm_struct(mm, vma);
+ if (unlikely(ret)) {
+ kmem_cache_free(vm_area_cachep, vma);
+ goto up_fail;
+ }
+
+ current->mm->context.vdso = (void *)addr;
+
+ mm->total_vm++;
+up_fail:
+ up_write(&mm->mmap_sem);
+ return ret;
+}
+
+const char *arch_vma_name(struct vm_area_struct *vma)
+{
+ if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
+ return "[vdso]";
+
+ return NULL;
+}
+
+struct vm_area_struct *get_gate_vma(struct task_struct *task)
+{
+ return NULL;
+}
+
+int in_gate_area(struct task_struct *task, unsigned long address)
+{
+ return 0;
+}
+
+int in_gate_area_no_task(unsigned long address)
+{
+ return 0;
+}
diff --git a/arch/sh/kernel/vsyscall/vsyscall.lds.S b/arch/sh/kernel/vsyscall/vsyscall.lds.S
new file mode 100644
index 00000000000..b13c3d439fe
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall.lds.S
@@ -0,0 +1,74 @@
+/*
+ * Linker script for vsyscall DSO. The vsyscall page is an ELF shared
+ * object prelinked to its virtual address, and with only one read-only
+ * segment (that fits in one page). This script controls its layout.
+ */
+#include <asm/asm-offsets.h>
+
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+OUTPUT_FORMAT("elf32-sh-linux", "elf32-sh-linux", "elf32-sh-linux")
+#else
+OUTPUT_FORMAT("elf32-shbig-linux", "elf32-shbig-linux", "elf32-shbig-linux")
+#endif
+OUTPUT_ARCH(sh)
+
+/* The ELF entry point can be used to set the AT_SYSINFO value. */
+ENTRY(__kernel_vsyscall);
+
+SECTIONS
+{
+ . = SIZEOF_HEADERS;
+
+ .hash : { *(.hash) } :text
+ .gnu.hash : { *(.gnu.hash) }
+ .dynsym : { *(.dynsym) }
+ .dynstr : { *(.dynstr) }
+ .gnu.version : { *(.gnu.version) }
+ .gnu.version_d : { *(.gnu.version_d) }
+ .gnu.version_r : { *(.gnu.version_r) }
+
+ /* This linker script is used both with -r and with -shared.
+ For the layouts to match, we need to skip more than enough
+ space for the dynamic symbol table et al. If this amount
+ is insufficient, ld -shared will barf. Just increase it here. */
+ . = 0x400;
+
+ .text : { *(.text) } :text =0x90909090
+ .note : { *(.note.*) } :text :note
+ .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr
+ .eh_frame : { KEEP (*(.eh_frame)) } :text
+ .dynamic : { *(.dynamic) } :text :dynamic
+ .useless : {
+ *(.got.plt) *(.got)
+ *(.data .data.* .gnu.linkonce.d.*)
+ *(.dynbss)
+ *(.bss .bss.* .gnu.linkonce.b.*)
+ } :text
+}
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+ text PT_LOAD FILEHDR PHDRS FLAGS(5); /* PF_R|PF_X */
+ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
+ note PT_NOTE FLAGS(4); /* PF_R */
+ eh_frame_hdr 0x6474e550; /* PT_GNU_EH_FRAME, but ld doesn't match the name */
+}
+
+/*
+ * This controls what symbols we export from the DSO.
+ */
+VERSION
+{
+ LINUX_2.6 {
+ global:
+ __kernel_vsyscall;
+ __kernel_sigreturn;
+ __kernel_rt_sigreturn;
+
+ local: *;
+ };
+}
diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig
index b445d02075e..9dd606464d2 100644
--- a/arch/sh/mm/Kconfig
+++ b/arch/sh/mm/Kconfig
@@ -223,6 +223,19 @@ config 32BIT
32-bits through the SH-4A PMB. If this is not set, legacy
29-bit physical addressing will be used.
+config VSYSCALL
+ bool "Support vsyscall page"
+ depends on MMU
+ default y
+ help
+ This will enable support for the kernel mapping a vDSO page
+ in process space, and subsequently handing down the entry point
+ to the libc through the ELF auxiliary vector.
+
+ From the kernel side this is used for the signal trampoline.
+ For systems with an MMU that can afford to give up a page,
+ (the default value) say Y.
+
choice
prompt "HugeTLB page size"
depends on HUGETLB_PAGE && CPU_SH4 && MMU
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index ad182b31d84..7154d1ce978 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -286,6 +286,9 @@ void __init mem_init(void)
initsize >> 10);
p3_cache_init();
+
+ /* Initialize the vDSO */
+ vsyscall_init();
}
void free_initmem(void)
diff --git a/arch/sh/mm/tlb-flush.c b/arch/sh/mm/tlb-flush.c
index fd7e42bcaa4..73ec7f6084f 100644
--- a/arch/sh/mm/tlb-flush.c
+++ b/arch/sh/mm/tlb-flush.c
@@ -14,12 +14,12 @@
void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
{
- if (vma->vm_mm && vma->vm_mm->context != NO_CONTEXT) {
+ if (vma->vm_mm && vma->vm_mm->context.id != NO_CONTEXT) {
unsigned long flags;
unsigned long asid;
unsigned long saved_asid = MMU_NO_ASID;
- asid = vma->vm_mm->context & MMU_CONTEXT_ASID_MASK;
+ asid = vma->vm_mm->context.id & MMU_CONTEXT_ASID_MASK;
page &= PAGE_MASK;
local_irq_save(flags);
@@ -39,20 +39,21 @@ void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
{
struct mm_struct *mm = vma->vm_mm;
- if (mm->context != NO_CONTEXT) {
+ if (mm->context.id != NO_CONTEXT) {
unsigned long flags;
int size;
local_irq_save(flags);
size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
if (size > (MMU_NTLB_ENTRIES/4)) { /* Too many TLB to flush */
- mm->context = NO_CONTEXT;
+ mm->context.id = NO_CONTEXT;
if (mm == current->mm)
activate_context(mm);
} else {
- unsigned long asid = mm->context&MMU_CONTEXT_ASID_MASK;
+ unsigned long asid;
unsigned long saved_asid = MMU_NO_ASID;
+ asid = mm->context.id & MMU_CONTEXT_ASID_MASK;
start &= PAGE_MASK;
end += (PAGE_SIZE - 1);
end &= PAGE_MASK;
@@ -81,9 +82,10 @@ void flush_tlb_kernel_range(unsigned long start, unsigned long end)
if (size > (MMU_NTLB_ENTRIES/4)) { /* Too many TLB to flush */
flush_tlb_all();
} else {
- unsigned long asid = init_mm.context&MMU_CONTEXT_ASID_MASK;
+ unsigned long asid;
unsigned long saved_asid = get_asid();
+ asid = init_mm.context.id & MMU_CONTEXT_ASID_MASK;
start &= PAGE_MASK;
end += (PAGE_SIZE - 1);
end &= PAGE_MASK;
@@ -101,11 +103,11 @@ void flush_tlb_mm(struct mm_struct *mm)
{
/* Invalidate all TLB of this process. */
/* Instead of invalidating each TLB, we get new MMU context. */
- if (mm->context != NO_CONTEXT) {
+ if (mm->context.id != NO_CONTEXT) {
unsigned long flags;
local_irq_save(flags);
- mm->context = NO_CONTEXT;
+ mm->context.id = NO_CONTEXT;
if (mm == current->mm)
activate_context(mm);
local_irq_restore(flags);