Contributors: 26
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Linus Torvalds (pre-git) |
945 |
62.67% |
39 |
46.43% |
| David S. Miller |
308 |
20.42% |
8 |
9.52% |
| Mike Rapoport |
46 |
3.05% |
1 |
1.19% |
| Nicholas Piggin |
35 |
2.32% |
1 |
1.19% |
| Johannes Weiner |
27 |
1.79% |
1 |
1.19% |
| Kautuk Consul |
22 |
1.46% |
1 |
1.19% |
| Linus Torvalds |
21 |
1.39% |
3 |
3.57% |
| Peter Xu |
17 |
1.13% |
5 |
5.95% |
| Al Viro |
16 |
1.06% |
2 |
2.38% |
| Nadia Yvette Chambers |
13 |
0.86% |
1 |
1.19% |
| Sam Ravnborg |
11 |
0.73% |
4 |
4.76% |
| Michel Lespinasse |
7 |
0.46% |
1 |
1.19% |
| Khalid Aziz |
7 |
0.46% |
2 |
2.38% |
| Rob Radez |
6 |
0.40% |
1 |
1.19% |
| Christoph Hellwig |
3 |
0.20% |
1 |
1.19% |
| Shaohua Li |
3 |
0.20% |
1 |
1.19% |
| Eric W. Biedermann |
3 |
0.20% |
1 |
1.19% |
| Valdis Kletnieks |
3 |
0.20% |
1 |
1.19% |
| Guan Xuetao |
3 |
0.20% |
1 |
1.19% |
| Souptick Joarder |
3 |
0.20% |
1 |
1.19% |
| Pete Zaitcev |
3 |
0.20% |
2 |
2.38% |
| Adrian Bunk |
2 |
0.13% |
2 |
2.38% |
| Greg Kroah-Hartman |
1 |
0.07% |
1 |
1.19% |
| Kees Cook |
1 |
0.07% |
1 |
1.19% |
| Qi Zheng |
1 |
0.07% |
1 |
1.19% |
| David Hildenbrand |
1 |
0.07% |
1 |
1.19% |
| Total |
1508 |
|
84 |
|
// SPDX-License-Identifier: GPL-2.0
/*
* fault.c: Page fault handlers for the Sparc.
*
* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
* Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*/
#include <asm/head.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/ptrace.h>
#include <linux/mman.h>
#include <linux/threads.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/perf_event.h>
#include <linux/interrupt.h>
#include <linux/kdebug.h>
#include <linux/uaccess.h>
#include <linux/extable.h>
#include <asm/page.h>
#include <asm/openprom.h>
#include <asm/oplib.h>
#include <asm/setup.h>
#include <asm/smp.h>
#include <asm/traps.h>
#include "mm_32.h"
int show_unhandled_signals = 1;
static void __noreturn unhandled_fault(unsigned long address,
struct task_struct *tsk,
struct pt_regs *regs)
{
if ((unsigned long) address < PAGE_SIZE) {
printk(KERN_ALERT
"Unable to handle kernel NULL pointer dereference\n");
} else {
printk(KERN_ALERT "Unable to handle kernel paging request at virtual address %08lx\n",
address);
}
printk(KERN_ALERT "tsk->{mm,active_mm}->context = %08lx\n",
(tsk->mm ? tsk->mm->context : tsk->active_mm->context));
printk(KERN_ALERT "tsk->{mm,active_mm}->pgd = %08lx\n",
(tsk->mm ? (unsigned long) tsk->mm->pgd :
(unsigned long) tsk->active_mm->pgd));
die_if_kernel("Oops", regs);
}
static inline void
show_signal_msg(struct pt_regs *regs, int sig, int code,
unsigned long address, struct task_struct *tsk)
{
if (!unhandled_signal(tsk, sig))
return;
if (!printk_ratelimit())
return;
printk("%s%s[%d]: segfault at %lx ip %px (rpc %px) sp %px error %x",
task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
tsk->comm, task_pid_nr(tsk), address,
(void *)regs->pc, (void *)regs->u_regs[UREG_I7],
(void *)regs->u_regs[UREG_FP], code);
print_vma_addr(KERN_CONT " in ", regs->pc);
printk(KERN_CONT "\n");
}
static void __do_fault_siginfo(int code, int sig, struct pt_regs *regs,
unsigned long addr)
{
if (unlikely(show_unhandled_signals))
show_signal_msg(regs, sig, code,
addr, current);
force_sig_fault(sig, code, (void __user *) addr);
}
static unsigned long compute_si_addr(struct pt_regs *regs, int text_fault)
{
unsigned int insn;
if (text_fault)
return regs->pc;
if (regs->psr & PSR_PS)
insn = *(unsigned int *) regs->pc;
else
__get_user(insn, (unsigned int *) regs->pc);
return safe_compute_effective_address(regs, insn);
}
static noinline void do_fault_siginfo(int code, int sig, struct pt_regs *regs,
int text_fault)
{
unsigned long addr = compute_si_addr(regs, text_fault);
__do_fault_siginfo(code, sig, regs, addr);
}
asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
unsigned long address)
{
struct vm_area_struct *vma;
struct task_struct *tsk = current;
struct mm_struct *mm = tsk->mm;
int from_user = !(regs->psr & PSR_PS);
int code;
vm_fault_t fault;
unsigned int flags = FAULT_FLAG_DEFAULT;
if (text_fault)
address = regs->pc;
/*
* We fault-in kernel-space virtual memory on-demand. The
* 'reference' page table is init_mm.pgd.
*
* NOTE! We MUST NOT take any locks for this case. We may
* be in an interrupt or a critical region, and should
* only copy the information from the master page table,
* nothing more.
*/
code = SEGV_MAPERR;
if (address >= TASK_SIZE)
goto vmalloc_fault;
/*
* If we're in an interrupt or have no user
* context, we must not take the fault..
*/
if (pagefault_disabled() || !mm)
goto no_context;
if (!from_user && address >= PAGE_OFFSET)
goto no_context;
perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
retry:
vma = lock_mm_and_find_vma(mm, address, regs);
if (!vma)
goto bad_area_nosemaphore;
/*
* Ok, we have a good vm_area for this memory access, so
* we can handle it..
*/
code = SEGV_ACCERR;
if (write) {
if (!(vma->vm_flags & VM_WRITE))
goto bad_area;
} else {
/* Allow reads even for write-only mappings */
if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
goto bad_area;
}
if (from_user)
flags |= FAULT_FLAG_USER;
if (write)
flags |= FAULT_FLAG_WRITE;
/*
* If for any reason at all we couldn't handle the fault,
* make sure we exit gracefully rather than endlessly redo
* the fault.
*/
fault = handle_mm_fault(vma, address, flags, regs);
if (fault_signal_pending(fault, regs)) {
if (!from_user)
goto no_context;
return;
}
/* The fault is fully completed (including releasing mmap lock) */
if (fault & VM_FAULT_COMPLETED)
return;
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
else if (fault & VM_FAULT_SIGSEGV)
goto bad_area;
else if (fault & VM_FAULT_SIGBUS)
goto do_sigbus;
BUG();
}
if (fault & VM_FAULT_RETRY) {
flags |= FAULT_FLAG_TRIED;
/* No need to mmap_read_unlock(mm) as we would
* have already released it in __lock_page_or_retry
* in mm/filemap.c.
*/
goto retry;
}
mmap_read_unlock(mm);
return;
/*
* Something tried to access memory that isn't in our memory map..
* Fix it, but check if it's kernel or user first..
*/
bad_area:
mmap_read_unlock(mm);
bad_area_nosemaphore:
/* User mode accesses just cause a SIGSEGV */
if (from_user) {
do_fault_siginfo(code, SIGSEGV, regs, text_fault);
return;
}
/* Is this in ex_table? */
no_context:
if (!from_user) {
const struct exception_table_entry *entry;
entry = search_exception_tables(regs->pc);
#ifdef DEBUG_EXCEPTIONS
printk("Exception: PC<%08lx> faddr<%08lx>\n",
regs->pc, address);
printk("EX_TABLE: insn<%08lx> fixup<%08x>\n",
regs->pc, entry->fixup);
#endif
regs->pc = entry->fixup;
regs->npc = regs->pc + 4;
return;
}
unhandled_fault(address, tsk, regs);
/*
* We ran out of memory, or some other thing happened to us that made
* us unable to handle the page fault gracefully.
*/
out_of_memory:
mmap_read_unlock(mm);
if (from_user) {
pagefault_out_of_memory();
return;
}
goto no_context;
do_sigbus:
mmap_read_unlock(mm);
do_fault_siginfo(BUS_ADRERR, SIGBUS, regs, text_fault);
if (!from_user)
goto no_context;
vmalloc_fault:
{
/*
* Synchronize this task's top level page-table
* with the 'reference' page table.
*/
int offset = pgd_index(address);
pgd_t *pgd, *pgd_k;
p4d_t *p4d, *p4d_k;
pud_t *pud, *pud_k;
pmd_t *pmd, *pmd_k;
pgd = tsk->active_mm->pgd + offset;
pgd_k = init_mm.pgd + offset;
if (!pgd_present(*pgd)) {
if (!pgd_present(*pgd_k))
goto bad_area_nosemaphore;
pgd_val(*pgd) = pgd_val(*pgd_k);
return;
}
p4d = p4d_offset(pgd, address);
pud = pud_offset(p4d, address);
pmd = pmd_offset(pud, address);
p4d_k = p4d_offset(pgd_k, address);
pud_k = pud_offset(p4d_k, address);
pmd_k = pmd_offset(pud_k, address);
if (pmd_present(*pmd) || !pmd_present(*pmd_k))
goto bad_area_nosemaphore;
*pmd = *pmd_k;
return;
}
}
/* This always deals with user addresses. */
static void force_user_fault(unsigned long address, int write)
{
struct vm_area_struct *vma;
struct task_struct *tsk = current;
struct mm_struct *mm = tsk->mm;
unsigned int flags = FAULT_FLAG_USER;
int code;
code = SEGV_MAPERR;
vma = lock_mm_and_find_vma(mm, address, NULL);
if (!vma)
goto bad_area_nosemaphore;
code = SEGV_ACCERR;
if (write) {
if (!(vma->vm_flags & VM_WRITE))
goto bad_area;
flags |= FAULT_FLAG_WRITE;
} else {
if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
goto bad_area;
}
switch (handle_mm_fault(vma, address, flags, NULL)) {
case VM_FAULT_SIGBUS:
case VM_FAULT_OOM:
goto do_sigbus;
}
mmap_read_unlock(mm);
return;
bad_area:
mmap_read_unlock(mm);
bad_area_nosemaphore:
__do_fault_siginfo(code, SIGSEGV, tsk->thread.kregs, address);
return;
do_sigbus:
mmap_read_unlock(mm);
__do_fault_siginfo(BUS_ADRERR, SIGBUS, tsk->thread.kregs, address);
}
static void check_stack_aligned(unsigned long sp)
{
if (sp & 0x7UL)
force_sig(SIGILL);
}
void window_overflow_fault(void)
{
unsigned long sp;
sp = current_thread_info()->rwbuf_stkptrs[0];
if (((sp + 0x38) & PAGE_MASK) != (sp & PAGE_MASK))
force_user_fault(sp + 0x38, 1);
force_user_fault(sp, 1);
check_stack_aligned(sp);
}
void window_underflow_fault(unsigned long sp)
{
if (((sp + 0x38) & PAGE_MASK) != (sp & PAGE_MASK))
force_user_fault(sp + 0x38, 0);
force_user_fault(sp, 0);
check_stack_aligned(sp);
}
void window_ret_fault(struct pt_regs *regs)
{
unsigned long sp;
sp = regs->u_regs[UREG_FP];
if (((sp + 0x38) & PAGE_MASK) != (sp & PAGE_MASK))
force_user_fault(sp + 0x38, 0);
force_user_fault(sp, 0);
check_stack_aligned(sp);
}