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23 October 2021, 00:29:24 UTC
Revision bf85fa6c878aa3968df47d7f70a2b506c3e53b99 authored by Anton W\xf6llert on 27 July 2005, 07:45:17 UTC, committed by Linus Torvalds on 27 July 2005, 23:34:34 UTC 
[PATCH] ppc32: 8xx avoid icbi misbehaviour in __flush_dcache_icache_phys
 
On 8xx, in the case where a pagefault happens for a process who's not
the owner of the vma in question (ptrace for instance), the flush
operation is performed via the physical address.

Unfortunately, that results in a strange, unexplainable "icbi"
instruction fault, most likely due to a CPU bug (see oops below).

Avoid that by flushing the page via its kernel virtual address.

Oops: kernel access of bad area, sig: 11 [#2]
NIP: C000543C LR: C000B060 SP: C0F35DF0 REGS: c0f35d40 TRAP: 0300 Not tainted
MSR: 00009022 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 10
DAR: 00000010, DSISR: C2000000
TASK = c0ea8430[761] 'gdbserver' THREAD: c0f34000
Last syscall: 26
GPR00: 00009022 C0F35DF0 C0EA8430 00F59000 00000100 FFFFFFFF 00F58000
00000001
GPR08: C021DAEF C0270000 00009032 C0270000 22044024 10025428 01000800
00000001
GPR16: 007FFF3F 00000001 00000000 7FBC6AC0 00F61022 00000001 C0839300
C01E0000
GPR24: 00CD0889 C082F568 3000AC18 C02A7A00 C0EA15C8 00F588A9 C02ACB00
C02ACB00
NIP [c000543c] __flush_dcache_icache_phys+0x38/0x54
LR [c000b060] flush_dcache_icache_page+0x20/0x30
Call trace:
[c000b154] update_mmu_cache+0x7c/0xa4
[c005ae98] do_wp_page+0x460/0x5ec
[c005c8a0] handle_mm_fault+0x7cc/0x91c
[c005ccec] get_user_pages+0x2fc/0x65c
[c0027104] access_process_vm+0x9c/0x1d4
[c00076e0] sys_ptrace+0x240/0x4a4
[c0002bd0] ret_from_syscall+0x0/0x44

Signed-off-by: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1 parent 5990415
Raw File
Tip revision: bf85fa6c878aa3968df47d7f70a2b506c3e53b99 authored by Anton W\xf6llert on 27 July 2005, 07:45:17 UTC
[PATCH] ppc32: 8xx avoid icbi misbehaviour in __flush_dcache_icache_phys
Tip revision: bf85fa6
sys_ni.c 

#include <linux/linkage.h>
#include <linux/errno.h>

#include <asm/unistd.h>

/*
 * Non-implemented system calls get redirected here.
 */
asmlinkage long sys_ni_syscall(void)
{
	return -ENOSYS;
}

cond_syscall(sys_nfsservctl);
cond_syscall(sys_quotactl);
cond_syscall(sys_acct);
cond_syscall(sys_lookup_dcookie);
cond_syscall(sys_swapon);
cond_syscall(sys_swapoff);
cond_syscall(sys_kexec_load);
cond_syscall(compat_sys_kexec_load);
cond_syscall(sys_init_module);
cond_syscall(sys_delete_module);
cond_syscall(sys_socketpair);
cond_syscall(sys_bind);
cond_syscall(sys_listen);
cond_syscall(sys_accept);
cond_syscall(sys_connect);
cond_syscall(sys_getsockname);
cond_syscall(sys_getpeername);
cond_syscall(sys_sendto);
cond_syscall(sys_send);
cond_syscall(sys_recvfrom);
cond_syscall(sys_recv);
cond_syscall(sys_socket);
cond_syscall(sys_setsockopt);
cond_syscall(sys_getsockopt);
cond_syscall(sys_shutdown);
cond_syscall(sys_sendmsg);
cond_syscall(sys_recvmsg);
cond_syscall(sys_socketcall);
cond_syscall(sys_futex);
cond_syscall(compat_sys_futex);
cond_syscall(sys_epoll_create);
cond_syscall(sys_epoll_ctl);
cond_syscall(sys_epoll_wait);
cond_syscall(sys_semget);
cond_syscall(sys_semop);
cond_syscall(sys_semtimedop);
cond_syscall(sys_semctl);
cond_syscall(sys_msgget);
cond_syscall(sys_msgsnd);
cond_syscall(sys_msgrcv);
cond_syscall(sys_msgctl);
cond_syscall(sys_shmget);
cond_syscall(sys_shmat);
cond_syscall(sys_shmdt);
cond_syscall(sys_shmctl);
cond_syscall(sys_mq_open);
cond_syscall(sys_mq_unlink);
cond_syscall(sys_mq_timedsend);
cond_syscall(sys_mq_timedreceive);
cond_syscall(sys_mq_notify);
cond_syscall(sys_mq_getsetattr);
cond_syscall(compat_sys_mq_open);
cond_syscall(compat_sys_mq_timedsend);
cond_syscall(compat_sys_mq_timedreceive);
cond_syscall(compat_sys_mq_notify);
cond_syscall(compat_sys_mq_getsetattr);
cond_syscall(sys_mbind);
cond_syscall(sys_get_mempolicy);
cond_syscall(sys_set_mempolicy);
cond_syscall(compat_sys_mbind);
cond_syscall(compat_sys_get_mempolicy);
cond_syscall(compat_sys_set_mempolicy);
cond_syscall(sys_add_key);
cond_syscall(sys_request_key);
cond_syscall(sys_keyctl);
cond_syscall(compat_sys_keyctl);
cond_syscall(compat_sys_socketcall);
cond_syscall(sys_set_zone_reclaim);
cond_syscall(sys_inotify_init);
cond_syscall(sys_inotify_add_watch);
cond_syscall(sys_inotify_rm_watch);

/* arch-specific weak syscall entries */
cond_syscall(sys_pciconfig_read);
cond_syscall(sys_pciconfig_write);
cond_syscall(sys_pciconfig_iobase);
cond_syscall(sys32_ipc);
cond_syscall(sys32_sysctl);
cond_syscall(ppc_rtas);
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