Signed-off-by: Johannes Berg <johannes.b...@intel.com>
---
arch/um/include/asm/Kbuild | 1 -
arch/um/include/asm/mm_hooks.h | 22 ++++++
arch/um/include/asm/mmu.h | 3 +-
arch/um/include/asm/mmu_context.h | 2 +-
arch/um/include/shared/os.h | 1 -
arch/um/kernel/process.c | 3 -
arch/um/kernel/skas/mmu.c | 35 ++++++----
arch/um/kernel/tlb.c | 5 +-
arch/um/os-Linux/skas/process.c | 107 ------------------------------
arch/x86/um/ldt.c | 53 +++++++--------
10 files changed, 76 insertions(+), 156 deletions(-)
create mode 100644 arch/um/include/asm/mm_hooks.h
diff --git a/arch/um/include/asm/Kbuild b/arch/um/include/asm/Kbuild
index b2d834a29f3a..de8d82a6fd7b 100644
--- a/arch/um/include/asm/Kbuild
+++ b/arch/um/include/asm/Kbuild
@@ -26,5 +26,4 @@ generic-y += switch_to.h
generic-y += topology.h
generic-y += trace_clock.h
generic-y += kprobes.h
-generic-y += mm_hooks.h
generic-y += vga.h
diff --git a/arch/um/include/asm/mm_hooks.h b/arch/um/include/asm/mm_hooks.h
new file mode 100644
index 000000000000..b1016520c5b8
--- /dev/null
+++ b/arch/um/include/asm/mm_hooks.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_UM_MM_HOOKS_H
+#define _ASM_UM_MM_HOOKS_H
+
+int arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm);
+
+static inline void arch_exit_mmap(struct mm_struct *mm)
+{
+}
+
+static inline void arch_unmap(struct mm_struct *mm,
+ unsigned long start, unsigned long end)
+{
+}
+
+static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
+ bool write, bool execute, bool foreign)
+{
+ /* by default, allow everything */
+ return true;
+}
+#endif /* _ASM_UM_MM_HOOKS_H */
diff --git a/arch/um/include/asm/mmu.h b/arch/um/include/asm/mmu.h
index 5b072aba5b65..68a710d23b5d 100644
--- a/arch/um/include/asm/mmu.h
+++ b/arch/um/include/asm/mmu.h
@@ -18,7 +18,8 @@ typedef struct mm_context {
extern void __switch_mm(struct mm_id * mm_idp);
/* Avoid tangled inclusion with asm/ldt.h */
-extern long init_new_ldt(struct mm_context *to_mm, struct mm_context *from_mm);
+extern int init_new_ldt(struct mm_context *to_mm);
+extern int copy_ldt(struct mm_context *to_mm, struct mm_context *from_mm);
extern void free_ldt(struct mm_context *mm);
#endif
diff --git a/arch/um/include/asm/mmu_context.h
b/arch/um/include/asm/mmu_context.h
index 68e2eb9cfb47..8668861d4a85 100644
--- a/arch/um/include/asm/mmu_context.h
+++ b/arch/um/include/asm/mmu_context.h
@@ -13,7 +13,7 @@
#include <asm/mm_hooks.h>
#include <asm/mmu.h>
-extern void force_flush_all(void);
+void force_flush_all(struct mm_struct *mm);
#define activate_mm activate_mm
static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h
index 1a82c6548dd5..c9acc28fe47c 100644
--- a/arch/um/include/shared/os.h
+++ b/arch/um/include/shared/os.h
@@ -289,7 +289,6 @@ extern int protect(struct mm_id * mm_idp, unsigned long
addr,
/* skas/process.c */
extern int is_skas_winch(int pid, int fd, void *data);
extern int start_userspace(unsigned long stub_stack);
-extern int copy_context_skas0(unsigned long stack, int pid);
extern void userspace(struct uml_pt_regs *regs, unsigned long *aux_fp_regs);
extern void new_thread(void *stack, jmp_buf *buf, void (*handler)(void));
extern void switch_threads(jmp_buf *me, jmp_buf *you);
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 6daffb9d8a8d..a024acd6d85c 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -25,7 +25,6 @@
#include <linux/threads.h>
#include <linux/resume_user_mode.h>
#include <asm/current.h>
-#include <asm/mmu_context.h>
#include <linux/uaccess.h>
#include <as-layout.h>
#include <kern_util.h>
@@ -139,8 +138,6 @@ void new_thread_handler(void)
/* Called magically, see new_thread_handler above */
void fork_handler(void)
{
- force_flush_all();
-
schedule_tail(current->thread.prev_sched);
/*
diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c
index 656fe16c9b63..ac4ca203ac24 100644
--- a/arch/um/kernel/skas/mmu.c
+++ b/arch/um/kernel/skas/mmu.c
@@ -10,13 +10,13 @@
#include <asm/pgalloc.h>
#include <asm/sections.h>
+#include <asm/mmu_context.h>
#include <as-layout.h>
#include <os.h>
#include <skas.h>
int init_new_context(struct task_struct *task, struct mm_struct *mm)
{
- struct mm_context *from_mm = NULL;
struct mm_context *to_mm = &mm->context;
unsigned long stack = 0;
int ret = -ENOMEM;
@@ -26,14 +26,13 @@ int init_new_context(struct task_struct *task, struct
mm_struct *mm)
goto out;
to_mm->id.stack = stack;
- if (current->mm != NULL && current->mm != &init_mm)
- from_mm = ¤t->mm->context;
+ /*
+ * Allocate a completely fresh mm. We'll sync the mappings once
+ * the rest of the kernel is done, in arch_copy_mm().
+ */
block_signals_trace();
- if (from_mm)
- to_mm->id.u.pid = copy_context_skas0(stack,
- from_mm->id.u.pid);
- else to_mm->id.u.pid = start_userspace(stack);
+ to_mm->id.u.pid = start_userspace(stack);
unblock_signals_trace();
if (to_mm->id.u.pid < 0) {
@@ -41,12 +40,9 @@ int init_new_context(struct task_struct *task, struct
mm_struct *mm)
goto out_free;
}
- ret = init_new_ldt(to_mm, from_mm);
- if (ret < 0) {
- printk(KERN_ERR "init_new_context_skas - init_ldt"
- " failed, errno = %d\n", ret);
+ ret = init_new_ldt(to_mm);
+ if (ret)
goto out_free;
- }
return 0;
@@ -57,6 +53,21 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm)
return ret;
}
+int arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
+{
+ int ret = copy_ldt(&mm->context, &oldmm->context);
+
+ if (ret < 0) {
+ printk(KERN_ERR "%s - copy_ldt failed, errno = %d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ force_flush_all(mm);
+ return 0;
+}
+
+
void destroy_context(struct mm_struct *mm)
{
struct mm_context *mmu = &mm->context;
diff --git a/arch/um/kernel/tlb.c b/arch/um/kernel/tlb.c
index 34ec8e677fb9..7c0161321fd9 100644
--- a/arch/um/kernel/tlb.c
+++ b/arch/um/kernel/tlb.c
@@ -600,14 +600,11 @@ void flush_tlb_mm(struct mm_struct *mm)
fix_range(mm, vma->vm_start, vma->vm_end, 0);
}
-void force_flush_all(void)
+void force_flush_all(struct mm_struct *mm)
{
- struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
VMA_ITERATOR(vmi, mm, 0);
- mmap_read_lock(mm);
for_each_vma(vmi, vma)
fix_range(mm, vma->vm_start, vma->vm_end, 1);
- mmap_read_unlock(mm);
}
diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index f92129bbf981..403f4c6082b6 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -508,113 +508,6 @@ void userspace(struct uml_pt_regs *regs, unsigned long
*aux_fp_regs)
}
}
-static unsigned long thread_regs[MAX_REG_NR];
-static unsigned long thread_fp_regs[FP_SIZE];
-
-static int __init init_thread_regs(void)
-{
- get_safe_registers(thread_regs, thread_fp_regs);
- /* Set parent's instruction pointer to start of clone-stub */
- thread_regs[REGS_IP_INDEX] = STUB_CODE +
- (unsigned long) stub_clone_handler -
- (unsigned long) __syscall_stub_start;
- thread_regs[REGS_SP_INDEX] = STUB_DATA + STUB_DATA_PAGES *
UM_KERN_PAGE_SIZE -
- sizeof(void *);
-#ifdef __SIGNAL_FRAMESIZE
- thread_regs[REGS_SP_INDEX] -= __SIGNAL_FRAMESIZE;
-#endif
- return 0;
-}
-
-__initcall(init_thread_regs);
-
-int copy_context_skas0(unsigned long new_stack, int pid)
-{
- int err;
- unsigned long current_stack = current_stub_stack();
- struct stub_data *data = (struct stub_data *) current_stack;
- struct stub_data *child_data = (struct stub_data *) new_stack;
- unsigned long long new_offset;
- int new_fd = phys_mapping(uml_to_phys((void *)new_stack), &new_offset);
-
- /*
- * prepare offset and fd of child's stack as argument for parent's
- * and child's mmap2 calls
- */
- *data = ((struct stub_data) {
- .offset = MMAP_OFFSET(new_offset),
- .fd = new_fd,
- .parent_err = -ESRCH,
- .child_err = 0,
- });
-
- *child_data = ((struct stub_data) {
- .child_err = -ESRCH,
- });
-
- err = ptrace_setregs(pid, thread_regs);
- if (err < 0) {
- err = -errno;
- printk(UM_KERN_ERR "%s : PTRACE_SETREGS failed, pid = %d, errno =
%d\n",
- __func__, pid, -err);
- return err;
- }
-
- err = put_fp_registers(pid, thread_fp_regs);
- if (err < 0) {
- printk(UM_KERN_ERR "%s : put_fp_registers failed, pid = %d, err =
%d\n",
- __func__, pid, err);
- return err;
- }
-
- /*
- * Wait, until parent has finished its work: read child's pid from
- * parent's stack, and check, if bad result.
- */
- err = ptrace(PTRACE_CONT, pid, 0, 0);
- if (err) {
- err = -errno;
- printk(UM_KERN_ERR "Failed to continue new process, pid = %d, errno
= %d\n",
- pid, errno);
- return err;
- }
-
- wait_stub_done(pid);
-
- pid = data->parent_err;
- if (pid < 0) {
- printk(UM_KERN_ERR "%s - stub-parent reports error %d\n",
- __func__, -pid);
- return pid;
- }
-
- /*
- * Wait, until child has finished too: read child's result from
- * child's stack and check it.
- */
- wait_stub_done(pid);
- if (child_data->child_err != STUB_DATA) {
- printk(UM_KERN_ERR "%s - stub-child %d reports error %ld\n",
- __func__, pid, data->child_err);
- err = data->child_err;
- goto out_kill;
- }
-
- if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL,
- (void *)PTRACE_O_TRACESYSGOOD) < 0) {
- err = -errno;
- printk(UM_KERN_ERR "%s : PTRACE_OLDSETOPTIONS failed, errno =
%d\n",
- __func__, errno);
- goto out_kill;
- }
-
- return pid;
-
- out_kill:
- os_kill_ptraced_process(pid, 1);
- return err;
-}
-
void new_thread(void *stack, jmp_buf *buf, void (*handler)(void))
{
(*buf)[0].JB_IP = (unsigned long) handler;
diff --git a/arch/x86/um/ldt.c b/arch/x86/um/ldt.c
index 255a44dd415a..609feaeff23b 100644
--- a/arch/x86/um/ldt.c
+++ b/arch/x86/um/ldt.c
@@ -297,36 +297,37 @@ static void ldt_get_host_info(void)
free_pages((unsigned long)ldt, order);
}
-long init_new_ldt(struct mm_context *new_mm, struct mm_context *from_mm)
+int init_new_ldt(struct mm_context *new_mm)
{
- struct user_desc desc;
+ struct user_desc desc = {};
short * num_p;
- int i;
- long page, err=0;
+ int err = 0;
void *addr = NULL;
-
mutex_init(&new_mm->arch.ldt.lock);
- if (!from_mm) {
- memset(&desc, 0, sizeof(desc));
- /*
- * Now we try to retrieve info about the ldt, we
- * inherited from the host. All ldt-entries found
- * will be reset in the following loop
- */
- ldt_get_host_info();
- for (num_p=host_ldt_entries; *num_p != -1; num_p++) {
- desc.entry_number = *num_p;
- err = write_ldt_entry(&new_mm->id, 1, &desc,
- &addr, *(num_p + 1) == -1);
- if (err)
- break;
- }
- new_mm->arch.ldt.entry_count = 0;
-
- goto out;
+ memset(&desc, 0, sizeof(desc));
+ /*
+ * Now we try to retrieve info about the ldt, we
+ * inherited from the host. All ldt-entries found
+ * will be reset in the following loop
+ */
+ ldt_get_host_info();
+ for (num_p=host_ldt_entries; *num_p != -1; num_p++) {
+ desc.entry_number = *num_p;
+ err = write_ldt_entry(&new_mm->id, 1, &desc,
+ &addr, *(num_p + 1) == -1);
+ if (err)
+ break;
}
+ new_mm->arch.ldt.entry_count = 0;
+
+ return err;
+}
+
+int copy_ldt(struct mm_context *new_mm, struct mm_context *from_mm)
+{
+ int err = 0;
/*
* Our local LDT is used to supply the data for
@@ -339,7 +340,9 @@ long init_new_ldt(struct mm_context *new_mm, struct
mm_context *from_mm)
memcpy(new_mm->arch.ldt.u.entries, from_mm->arch.ldt.u.entries,
sizeof(new_mm->arch.ldt.u.entries));
else {
- i = from_mm->arch.ldt.entry_count / LDT_ENTRIES_PER_PAGE;
+ int i = from_mm->arch.ldt.entry_count / LDT_ENTRIES_PER_PAGE;
+ unsigned long page;
+
while (i-->0) {
page = __get_free_page(GFP_KERNEL|__GFP_ZERO);
if (!page) {
@@ -355,11 +358,9 @@ long init_new_ldt(struct mm_context *new_mm, struct
mm_context *from_mm)
new_mm->arch.ldt.entry_count = from_mm->arch.ldt.entry_count;
mutex_unlock(&from_mm->arch.ldt.lock);
- out:
return err;
}
-
void free_ldt(struct mm_context *mm)
{
int i;
