From 64597f9dae1850e0360ae2e9b5485d4b5d1fdf4c Mon Sep 17 00:00:00 2001 From: Michael Mueller <mimu@linux.vnet.ibm.com> Date: Tue, 2 Jul 2013 22:58:26 +0200 Subject: s390/ptrace: PTRACE_TE_ABORT_RAND The patch implements a s390 specific ptrace request PTRACE_TE_ABORT_RAND to modify the randomness of spontaneous aborts of memory transactions of the transaction execution facility. The data argument of the ptrace request is used to specify the levels of randomness, 0 for normal operation, 1 to abort every transaction at a random instruction, and 2 to abort a random transaction at a random instruction. The default is 0 for normal operation. Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> --- arch/s390/kernel/ptrace.c | 50 ++++++++++++++++++++++++++++++++++++----------- 1 file changed, 39 insertions(+), 11 deletions(-) (limited to 'arch/s390/kernel') diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c index a314c57f4e94..e9fadb04e3c6 100644 --- a/arch/s390/kernel/ptrace.c +++ b/arch/s390/kernel/ptrace.c @@ -47,7 +47,7 @@ enum s390_regset { REGSET_GENERAL_EXTENDED, }; -void update_per_regs(struct task_struct *task) +void update_cr_regs(struct task_struct *task) { struct pt_regs *regs = task_pt_regs(task); struct thread_struct *thread = &task->thread; @@ -56,17 +56,25 @@ void update_per_regs(struct task_struct *task) #ifdef CONFIG_64BIT /* Take care of the enable/disable of transactional execution. */ if (MACHINE_HAS_TE) { - unsigned long cr0, cr0_new; + unsigned long cr[3], cr_new[3]; - __ctl_store(cr0, 0, 0); - /* set or clear transaction execution bits 8 and 9. */ + __ctl_store(cr, 0, 2); + cr_new[1] = cr[1]; + /* Set or clear transaction execution TXC/PIFO bits 8 and 9. */ if (task->thread.per_flags & PER_FLAG_NO_TE) - cr0_new = cr0 & ~(3UL << 54); + cr_new[0] = cr[0] & ~(3UL << 54); else - cr0_new = cr0 | (3UL << 54); - /* Only load control register 0 if necessary. */ - if (cr0 != cr0_new) - __ctl_load(cr0_new, 0, 0); + cr_new[0] = cr[0] | (3UL << 54); + /* Set or clear transaction execution TDC bits 62 and 63. */ + cr_new[2] = cr[2] & ~3UL; + if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND) { + if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND_TEND) + cr_new[2] |= 1UL; + else + cr_new[2] |= 2UL; + } + if (memcmp(&cr_new, &cr, sizeof(cr))) + __ctl_load(cr_new, 0, 2); } #endif /* Copy user specified PER registers */ @@ -100,14 +108,14 @@ void user_enable_single_step(struct task_struct *task) { set_tsk_thread_flag(task, TIF_SINGLE_STEP); if (task == current) - update_per_regs(task); + update_cr_regs(task); } void user_disable_single_step(struct task_struct *task) { clear_tsk_thread_flag(task, TIF_SINGLE_STEP); if (task == current) - update_per_regs(task); + update_cr_regs(task); } /* @@ -447,6 +455,26 @@ long arch_ptrace(struct task_struct *child, long request, if (!MACHINE_HAS_TE) return -EIO; child->thread.per_flags |= PER_FLAG_NO_TE; + child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND; + return 0; + case PTRACE_TE_ABORT_RAND: + if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE)) + return -EIO; + switch (data) { + case 0UL: + child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND; + break; + case 1UL: + child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND; + child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND; + break; + case 2UL: + child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND; + child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND; + break; + default: + return -EINVAL; + } return 0; default: /* Removing high order bit from addr (only for 31 bit). */ -- cgit v1.2.3 From 191a2fa0a8d2bbb64c98f9b1976fcb37ee5eae6b Mon Sep 17 00:00:00 2001 From: Michael Holzheu <holzheu@linux.vnet.ibm.com> Date: Thu, 18 Jul 2013 12:18:27 +0200 Subject: s390/kdump: Allow copy_oldmem_page() copy to virtual memory The kdump mmap patch series (git commit 83086978c63afd7c73e1c) changed the requirements for copy_oldmem_page(). Now this function is used for copying to virtual memory. So implement vmalloc support for the s390 version of copy_oldmem_page(). Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> --- arch/s390/kernel/crash_dump.c | 51 +++++++++++++++++++++++++++++++++++++++---- 1 file changed, 47 insertions(+), 4 deletions(-) (limited to 'arch/s390/kernel') diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index f703d91bf720..d8f355657171 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -21,6 +21,48 @@ #define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y))) #define PTR_DIFF(x, y) ((unsigned long)(((char *) (x)) - ((unsigned long) (y)))) + +/* + * Return physical address for virtual address + */ +static inline void *load_real_addr(void *addr) +{ + unsigned long real_addr; + + asm volatile( + " lra %0,0(%1)\n" + " jz 0f\n" + " la %0,0\n" + "0:" + : "=a" (real_addr) : "a" (addr) : "cc"); + return (void *)real_addr; +} + +/* + * Copy up to one page to vmalloc or real memory + */ +static ssize_t copy_page_real(void *buf, void *src, size_t csize) +{ + size_t size; + + if (is_vmalloc_addr(buf)) { + BUG_ON(csize >= PAGE_SIZE); + /* If buf is not page aligned, copy first part */ + size = min(roundup(__pa(buf), PAGE_SIZE) - __pa(buf), csize); + if (size) { + if (memcpy_real(load_real_addr(buf), src, size)) + return -EFAULT; + buf += size; + src += size; + } + /* Copy second part */ + size = csize - size; + return (size) ? memcpy_real(load_real_addr(buf), src, size) : 0; + } else { + return memcpy_real(buf, src, csize); + } +} + /* * Copy one page from "oldmem" * @@ -32,6 +74,7 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, unsigned long offset, int userbuf) { unsigned long src; + int rc; if (!csize) return 0; @@ -43,11 +86,11 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, src < OLDMEM_BASE + OLDMEM_SIZE) src -= OLDMEM_BASE; if (userbuf) - copy_to_user_real((void __force __user *) buf, (void *) src, - csize); + rc = copy_to_user_real((void __force __user *) buf, + (void *) src, csize); else - memcpy_real(buf, (void *) src, csize); - return csize; + rc = copy_page_real(buf, (void *) src, csize); + return (rc == 0) ? csize : rc; } /* -- cgit v1.2.3