From 59da21398e680e8100625d689c8bebee6a139e93 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Thu, 27 Nov 2008 11:05:55 +0100 Subject: [S390] fix system call parameter functions. syscall_get_nr() currently returns a valid result only if the call chain of the traced process includes do_syscall_trace_enter(). But collect_syscall() can be called for any sleeping task, the result of syscall_get_nr() in general is completely bogus. To make syscall_get_nr() work for any sleeping task the traps field in pt_regs is replace with svcnr - the system call number the process is executing. If svcnr == 0 the process is not on a system call path. The syscall_get_arguments and syscall_set_arguments use regs->gprs[2] for the first system call parameter. This is incorrect since gprs[2] may have been overwritten with the system call number if the call chain includes do_syscall_trace_enter. Use regs->orig_gprs2 instead. Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/ptrace.h | 2 +- arch/s390/include/asm/syscall.h | 28 ++++++++++++++++------------ 2 files changed, 17 insertions(+), 13 deletions(-) (limited to 'arch/s390/include/asm') diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h index a7226f8143f..fb0ca4796d3 100644 --- a/arch/s390/include/asm/ptrace.h +++ b/arch/s390/include/asm/ptrace.h @@ -321,8 +321,8 @@ struct pt_regs psw_t psw; unsigned long gprs[NUM_GPRS]; unsigned long orig_gpr2; + unsigned short svcnr; unsigned short ilc; - unsigned short trap; }; #endif diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h index 6e623971fbb..2429b87eb28 100644 --- a/arch/s390/include/asm/syscall.h +++ b/arch/s390/include/asm/syscall.h @@ -17,9 +17,7 @@ static inline long syscall_get_nr(struct task_struct *task, struct pt_regs *regs) { - if (regs->trap != __LC_SVC_OLD_PSW) - return -1; - return regs->gprs[2]; + return regs->svcnr ? regs->svcnr : -1; } static inline void syscall_rollback(struct task_struct *task, @@ -52,18 +50,20 @@ static inline void syscall_get_arguments(struct task_struct *task, unsigned int i, unsigned int n, unsigned long *args) { + unsigned long mask = -1UL; + BUG_ON(i + n > 6); #ifdef CONFIG_COMPAT - if (test_tsk_thread_flag(task, TIF_31BIT)) { - if (i + n == 6) - args[--n] = (u32) regs->args[0]; - while (n-- > 0) - args[n] = (u32) regs->gprs[2 + i + n]; - } + if (test_tsk_thread_flag(task, TIF_31BIT)) + mask = 0xffffffff; #endif if (i + n == 6) - args[--n] = regs->args[0]; - memcpy(args, ®s->gprs[2 + i], n * sizeof(args[0])); + args[--n] = regs->args[0] & mask; + while (n-- > 0) + if (i + n > 0) + args[n] = regs->gprs[2 + i + n] & mask; + if (i == 0) + args[0] = regs->orig_gpr2 & mask; } static inline void syscall_set_arguments(struct task_struct *task, @@ -74,7 +74,11 @@ static inline void syscall_set_arguments(struct task_struct *task, BUG_ON(i + n > 6); if (i + n == 6) regs->args[0] = args[--n]; - memcpy(®s->gprs[2 + i], args, n * sizeof(args[0])); + while (n-- > 0) + if (i + n > 0) + regs->gprs[2 + i + n] = args[n]; + if (i == 0) + regs->orig_gpr2 = args[0]; } #endif /* _ASM_SYSCALL_H */ -- cgit v1.2.3 From 2944a5c971c12766e2438ea407ec3567949c32b7 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Thu, 27 Nov 2008 11:05:57 +0100 Subject: [S390] pgtable.h: Fix oops in unmap_vmas for KVM processes When running several kvm processes with lots of memory overcommitment, we have seen an oops during process shutdown: ------------[ cut here ]------------ Kernel BUG at 0000000000193434 [verbose debug info unavailable] addressing exception: 0005 [#1] PREEMPT SMP Modules linked in: kvm sunrpc qeth_l2 dm_mod qeth ccwgroup CPU: 10 Not tainted 2.6.28-rc4-kvm-bigiron-00521-g0ccca08-dirty #8 Process kuli (pid: 14460, task: 0000000149822338, ksp: 0000000024f57650) Krnl PSW : 0704e00180000000 0000000000193434 (unmap_vmas+0x884/0xf10) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 EA:3 Krnl GPRS: 0000000000000002 0000000000000000 000000051008d000 000003e05e6034e0 00000000001933f6 00000000000001e9 0000000407259e0a 00000002be88c400 00000200001c1000 0000000407259608 0000000407259e08 0000000024f577f0 0000000407259e09 0000000000445fa8 00000000001933f6 0000000024f577f0 Krnl Code: 0000000000193426: eb22000c000d sllg %r2,%r2,12 000000000019342c: a7180000 lhi %r1,0 0000000000193430: b2290012 iske %r1,%r2 >0000000000193434: a7110002 tmll %r1,2 0000000000193438: a7840006 brc 8,193444 000000000019343c: 9602c000 oi 0(%r12),2 0000000000193440: 96806000 oi 0(%r6),128 0000000000193444: a7110004 tmll %r1,4 Call Trace: ([<00000000001933f6>] unmap_vmas+0x846/0xf10) [<0000000000199680>] exit_mmap+0x210/0x458 [<000000000012a8f8>] mmput+0x54/0xfc [<000000000012f714>] exit_mm+0x134/0x144 [<000000000013120c>] do_exit+0x240/0x878 [<00000000001318dc>] do_group_exit+0x98/0xc8 [<000000000013e6b0>] get_signal_to_deliver+0x30c/0x358 [<000000000010bee0>] do_signal+0xec/0x860 [<0000000000112e30>] sysc_sigpending+0xe/0x22 [<000002000013198a>] 0x2000013198a INFO: lockdep is turned off. Last Breaking-Event-Address: [<00000000001a68d0>] free_swap_and_cache+0x1a0/0x1a4 <4>---[ end trace bc19f1d51ac9db7c ]--- The faulting instruction is the storage key operation (iske) in ptep_rcp_copy (called by pte_clear, called by unmap_vmas). iske reads dirty and reference bit information for a physical page and requires a valid physical address. Since we are in pte_clear, we cannot rely on the pte containing a valid address. Fortunately we dont need these information in pte_clear - after all there is no mapping. The best fix is to remove the needless call to ptep_rcp_copy that contains the iske. Signed-off-by: Christian Borntraeger Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/pgtable.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'arch/s390/include/asm') diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 7fc76133b3e..5caddd4f7be 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -679,8 +679,6 @@ static inline void pmd_clear(pmd_t *pmd) static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - if (mm->context.has_pgste) - ptep_rcp_copy(ptep); pte_val(*ptep) = _PAGE_TYPE_EMPTY; if (mm->context.noexec) pte_val(ptep[PTRS_PER_PTE]) = _PAGE_TYPE_EMPTY; -- cgit v1.2.3 From 96b8936a9ed08746e47081458a5eb9e43a751e24 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 25 Nov 2008 08:10:03 +0100 Subject: remove __ARCH_WANT_COMPAT_SYS_PTRACE All architectures now use the generic compat_sys_ptrace, as should every new architecture that needs 32bit compat (if we'll ever get another). Remove the now superflous __ARCH_WANT_COMPAT_SYS_PTRACE define, and also kill a comment about __ARCH_SYS_PTRACE that was added after __ARCH_SYS_PTRACE was already gone. Signed-off-by: Christoph Hellwig Acked-by: David S. Miller Signed-off-by: Linus Torvalds --- arch/s390/include/asm/ptrace.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'arch/s390/include/asm') diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h index a7226f8143f..560ce8561df 100644 --- a/arch/s390/include/asm/ptrace.h +++ b/arch/s390/include/asm/ptrace.h @@ -486,8 +486,6 @@ struct task_struct; extern void user_enable_single_step(struct task_struct *); extern void user_disable_single_step(struct task_struct *); -#define __ARCH_WANT_COMPAT_SYS_PTRACE - #define user_mode(regs) (((regs)->psw.mask & PSW_MASK_PSTATE) != 0) #define instruction_pointer(regs) ((regs)->psw.addr & PSW_ADDR_INSN) #define user_stack_pointer(regs)((regs)->gprs[15]) -- cgit v1.2.3