From 8eb4bd666ffdca7171cd8118138a91842012b028 Mon Sep 17 00:00:00 2001 From: Michael Holzheu Date: Tue, 10 May 2011 17:13:39 +0200 Subject: [S390] kernel: Initialize register 14 when starting new CPU When starting a new CPU we currently jump to start_secondary() without setting register 14 (the return address) correctly. Therefore on the stack frame for start_secondary an invalid return address is stored. This leads to wrong stack back traces in kernel dumps. Example: #00 [1f33fe48] cpu_idle at 10614a #01 [1f33fe90] start_secondary at 54fa88 #02 [1f33feb8] (null) at 0 <--- invalid To fix this start_secondary() is called now with basr/brasl that sets register 14 correctly. The output of the stack backtrace looks then like the following: #00 [1f33fe48] cpu_idle at 10614a #01 [1f33fe90] start_secondary at 54fa88 #02 [1f33feb8] restart_base at 54f41e <--- correct Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/entry.S | 2 +- arch/s390/kernel/entry64.S | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'arch') diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index 648f64239a9..1b67fc6ebdc 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -836,7 +836,7 @@ restart_base: stosm __SF_EMPTY(%r15),0x04 # now we can turn dat on basr %r14,0 l %r14,restart_addr-.(%r14) - br %r14 # branch to start_secondary + basr %r14,%r14 # branch to start_secondary restart_addr: .long start_secondary .align 8 diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S index 9d3603d6c51..9fd86456349 100644 --- a/arch/s390/kernel/entry64.S +++ b/arch/s390/kernel/entry64.S @@ -841,7 +841,7 @@ restart_base: mvc __LC_SYSTEM_TIMER(8),__TI_system_timer(%r1) xc __LC_STEAL_TIMER(8),__LC_STEAL_TIMER stosm __SF_EMPTY(%r15),0x04 # now we can turn dat on - jg start_secondary + brasl %r14,start_secondary .align 8 restart_vtime: .long 0x7fffffff,0xffffffff -- cgit v1.2.3 From 91d378088b104f8e31baba8c518f32a7a219d58c Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Tue, 10 May 2011 17:13:40 +0200 Subject: [S390] disassembler: handle b280/spp instruction arch/s390/kvm/sie64a.S uses the b280 instruction. Tell the builtin disassembler to handle that code. Signed-off-by: Christian Borntraeger Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/dis.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch') diff --git a/arch/s390/kernel/dis.c b/arch/s390/kernel/dis.c index c83726c9fe0..3d4a78fc1ad 100644 --- a/arch/s390/kernel/dis.c +++ b/arch/s390/kernel/dis.c @@ -672,6 +672,7 @@ static struct insn opcode_b2[] = { { "rp", 0x77, INSTR_S_RD }, { "stcke", 0x78, INSTR_S_RD }, { "sacf", 0x79, INSTR_S_RD }, + { "spp", 0x80, INSTR_S_RD }, { "stsi", 0x7d, INSTR_S_RD }, { "srnm", 0x99, INSTR_S_RD }, { "stfpc", 0x9c, INSTR_S_RD }, -- cgit v1.2.3 From 83ace2701b81be549cca7af33c5b0499cb2602d6 Mon Sep 17 00:00:00 2001 From: Michael Holzheu Date: Tue, 10 May 2011 17:13:41 +0200 Subject: [S390] replace diag10() with diag10_range() function Currently the diag10() function can only release one page. For exploiters that have to call diag10 on a contiguous memory region this is suboptimal. This patch replaces the diag10() function with diag10_range() that is able to release multiple pages. In addition to that the new function now allows to release memory with addresses higher than 2047 MiB. This was due to a restriction of the diagnose implementation under z/VM prior to release 5.2. Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/diag.h | 17 +++++++++++++++-- arch/s390/kernel/diag.c | 21 --------------------- arch/s390/mm/cmm.c | 2 +- 3 files changed, 16 insertions(+), 24 deletions(-) (limited to 'arch') diff --git a/arch/s390/include/asm/diag.h b/arch/s390/include/asm/diag.h index 72b2e2f2d32..7e91c58072e 100644 --- a/arch/s390/include/asm/diag.h +++ b/arch/s390/include/asm/diag.h @@ -9,9 +9,22 @@ #define _ASM_S390_DIAG_H /* - * Diagnose 10: Release pages + * Diagnose 10: Release page range */ -extern void diag10(unsigned long addr); +static inline void diag10_range(unsigned long start_pfn, unsigned long num_pfn) +{ + unsigned long start_addr, end_addr; + + start_addr = start_pfn << PAGE_SHIFT; + end_addr = (start_pfn + num_pfn - 1) << PAGE_SHIFT; + + asm volatile( + "0: diag %0,%1,0x10\n" + "1:\n" + EX_TABLE(0b, 1b) + EX_TABLE(1b, 1b) + : : "a" (start_addr), "a" (end_addr)); +} /* * Diagnose 14: Input spool file manipulation diff --git a/arch/s390/kernel/diag.c b/arch/s390/kernel/diag.c index c032d11da8a..8237fc07ac7 100644 --- a/arch/s390/kernel/diag.c +++ b/arch/s390/kernel/diag.c @@ -8,27 +8,6 @@ #include #include -/* - * Diagnose 10: Release pages - */ -void diag10(unsigned long addr) -{ - if (addr >= 0x7ff00000) - return; - asm volatile( -#ifdef CONFIG_64BIT - " sam31\n" - " diag %0,%0,0x10\n" - "0: sam64\n" -#else - " diag %0,%0,0x10\n" - "0:\n" -#endif - EX_TABLE(0b, 0b) - : : "a" (addr)); -} -EXPORT_SYMBOL(diag10); - /* * Diagnose 14: Input spool file manipulation */ diff --git a/arch/s390/mm/cmm.c b/arch/s390/mm/cmm.c index c66ffd8dbbb..1f1dba9dcf5 100644 --- a/arch/s390/mm/cmm.c +++ b/arch/s390/mm/cmm.c @@ -91,7 +91,7 @@ static long cmm_alloc_pages(long nr, long *counter, } else free_page((unsigned long) npa); } - diag10(addr); + diag10_range(addr >> PAGE_SHIFT, 1); pa->pages[pa->index++] = addr; (*counter)++; spin_unlock(&cmm_lock); -- cgit v1.2.3 From 3d8dcb3c76bb2930798f61675c33cce8945ab988 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Tue, 10 May 2011 17:13:42 +0200 Subject: [S390] oprofile: fix min/max interval query checks oprofile_min_interval and oprofile_max_interval are unsigned, checking for negative values doesn't work. Change hwsampler_query_min_interval and hwsampler_query_max_interval to return an unsigned long and check for a zero value instead. Reported-by: Nicolas Kaiser Acked-by: Robert Richter Signed-off-by: Martin Schwidefsky --- arch/s390/oprofile/hwsampler.c | 14 ++++---------- arch/s390/oprofile/hwsampler.h | 4 ++-- arch/s390/oprofile/init.c | 8 ++------ 3 files changed, 8 insertions(+), 18 deletions(-) (limited to 'arch') diff --git a/arch/s390/oprofile/hwsampler.c b/arch/s390/oprofile/hwsampler.c index 4952872d6f0..33cbd373cce 100644 --- a/arch/s390/oprofile/hwsampler.c +++ b/arch/s390/oprofile/hwsampler.c @@ -1021,20 +1021,14 @@ deallocate_exit: return rc; } -long hwsampler_query_min_interval(void) +unsigned long hwsampler_query_min_interval(void) { - if (min_sampler_rate) - return min_sampler_rate; - else - return -EINVAL; + return min_sampler_rate; } -long hwsampler_query_max_interval(void) +unsigned long hwsampler_query_max_interval(void) { - if (max_sampler_rate) - return max_sampler_rate; - else - return -EINVAL; + return max_sampler_rate; } unsigned long hwsampler_get_sample_overflow_count(unsigned int cpu) diff --git a/arch/s390/oprofile/hwsampler.h b/arch/s390/oprofile/hwsampler.h index 8c72b59316b..1912f3bb190 100644 --- a/arch/s390/oprofile/hwsampler.h +++ b/arch/s390/oprofile/hwsampler.h @@ -102,8 +102,8 @@ int hwsampler_setup(void); int hwsampler_shutdown(void); int hwsampler_allocate(unsigned long sdbt, unsigned long sdb); int hwsampler_deallocate(void); -long hwsampler_query_min_interval(void); -long hwsampler_query_max_interval(void); +unsigned long hwsampler_query_min_interval(void); +unsigned long hwsampler_query_max_interval(void); int hwsampler_start_all(unsigned long interval); int hwsampler_stop_all(void); int hwsampler_deactivate(unsigned int cpu); diff --git a/arch/s390/oprofile/init.c b/arch/s390/oprofile/init.c index c63d7e58352..5995e9bc72d 100644 --- a/arch/s390/oprofile/init.c +++ b/arch/s390/oprofile/init.c @@ -145,15 +145,11 @@ static int oprofile_hwsampler_init(struct oprofile_operations *ops) * create hwsampler files only if hwsampler_setup() succeeds. */ oprofile_min_interval = hwsampler_query_min_interval(); - if (oprofile_min_interval < 0) { - oprofile_min_interval = 0; + if (oprofile_min_interval == 0) return -ENODEV; - } oprofile_max_interval = hwsampler_query_max_interval(); - if (oprofile_max_interval < 0) { - oprofile_max_interval = 0; + if (oprofile_max_interval == 0) return -ENODEV; - } if (oprofile_timer_init(ops)) return -ENODEV; -- cgit v1.2.3 From badb8bb983e9cf5b7a872e0a4f6ebeac2b1ce133 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Tue, 10 May 2011 17:13:43 +0200 Subject: [S390] fix alloc_pgste check in init_new_context Processes started with kernel_execve from a kernel thread will have current->mm==NULL. Reading current->mm->context.alloc_pgste will read a more or less random bit from lowcore in this case. If the bit turns out to be set the whole process tree started this way will allocate page table extensions although they have no need for it. Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/mmu_context.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h index a6f0e7cc9cd..8c277caa8d3 100644 --- a/arch/s390/include/asm/mmu_context.h +++ b/arch/s390/include/asm/mmu_context.h @@ -23,7 +23,7 @@ static inline int init_new_context(struct task_struct *tsk, #ifdef CONFIG_64BIT mm->context.asce_bits |= _ASCE_TYPE_REGION3; #endif - if (current->mm->context.alloc_pgste) { + if (current->mm && current->mm->context.alloc_pgste) { /* * alloc_pgste indicates, that any NEW context will be created * with extended page tables. The old context is unchanged. The -- cgit v1.2.3