From ae65a21fb851f09bf6341761d884fb86b644b75a Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 10 Nov 2016 10:46:47 -0800 Subject: lib/stackdepot: export save/fetch stack for drivers Some drivers would like to record stacktraces in order to aide leak tracing. As stackdepot already provides a facility for only storing the unique traces, thereby reducing the memory required, export that functionality for use by drivers. The code was originally created for KASAN and moved under lib in commit cd11016e5f521 ("mm, kasan: stackdepot implementation. Enable stackdepot for SLAB") so that it could be shared with mm/. In turn, we want to share it now with drivers. Link: http://lkml.kernel.org/r/20161108133209.22704-1-chris@chris-wilson.co.uk Signed-off-by: Chris Wilson Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Joonsoo Kim Cc: "Kirill A. Shutemov" Cc: Daniel Vetter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/stackdepot.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'lib') diff --git a/lib/stackdepot.c b/lib/stackdepot.c index 4d830e299989..f87d138e9672 100644 --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -192,6 +192,7 @@ void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace) trace->entries = stack->entries; trace->skip = 0; } +EXPORT_SYMBOL_GPL(depot_fetch_stack); /** * depot_save_stack - save stack in a stack depot. @@ -283,3 +284,4 @@ exit: fast_exit: return retval; } +EXPORT_SYMBOL_GPL(depot_save_stack); -- cgit v1.2.3 From 680bb946a1ae04fe0ff369a4965f76b48c07dc54 Mon Sep 17 00:00:00 2001 From: Abhi Das Date: Wed, 16 Nov 2016 21:44:23 -0600 Subject: fix iov_iter_advance() for ITER_PIPE iov_iter_advance() needs to decrement iter->count by the number of bytes we'd moved beyond. Normal flavours do that, but ITER_PIPE doesn't and ITER_PIPE generic_file_read_iter() for O_DIRECT files ends up with a bogus fallback to page cache read, resulting in incorrect values for file offset and bytes read. Signed-off-by: Abhi Das Signed-off-by: Al Viro --- lib/iov_iter.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/iov_iter.c b/lib/iov_iter.c index f0c7f1481bae..f2bd21b93dfc 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -683,10 +683,11 @@ static void pipe_advance(struct iov_iter *i, size_t size) struct pipe_inode_info *pipe = i->pipe; struct pipe_buffer *buf; int idx = i->idx; - size_t off = i->iov_offset; + size_t off = i->iov_offset, orig_sz; if (unlikely(i->count < size)) size = i->count; + orig_sz = size; if (size) { if (off) /* make it relative to the beginning of buffer */ @@ -713,6 +714,7 @@ static void pipe_advance(struct iov_iter *i, size_t size) pipe->nrbufs--; } } + i->count -= orig_sz; } void iov_iter_advance(struct iov_iter *i, size_t size) -- cgit v1.2.3 From e6b5f1be7afe1657c40c08082c562b1a036a54c1 Mon Sep 17 00:00:00 2001 From: Babu Moger Date: Wed, 2 Nov 2016 09:36:32 -0700 Subject: config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc This new config parameter limits the space used for "Lock debugging: prove locking correctness" by about 4MB. The current sparc systems have the limitation of 32MB size for kernel size including .text, .data and .bss sections. With PROVE_LOCKING feature, the kernel size could grow beyond this limit and causing system boot-up issues. With this option, kernel limits the size of the entries of lock_chains, stack_trace etc., so that kernel fits in required size limit. This is not visible to user and only used for sparc. Signed-off-by: Babu Moger Acked-by: Sam Ravnborg Signed-off-by: David S. Miller --- arch/sparc/Kconfig | 1 + lib/Kconfig.debug | 3 +++ 2 files changed, 4 insertions(+) (limited to 'lib') diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 60145c9b9f84..165ecdd24d22 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -43,6 +43,7 @@ config SPARC select ARCH_HAS_SG_CHAIN select CPU_NO_EFFICIENT_FFS select HAVE_ARCH_HARDENED_USERCOPY + select PROVE_LOCKING_SMALL if PROVE_LOCKING config SPARC32 def_bool !64BIT diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index b01e547d4d04..a6c8db1d62f6 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1085,6 +1085,9 @@ config PROVE_LOCKING For more details, see Documentation/locking/lockdep-design.txt. +config PROVE_LOCKING_SMALL + bool + config LOCKDEP bool depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT -- cgit v1.2.3