search for: kmemcheck

Hi On Fri, 27 Feb 2009 22:39:06 +0100 Vegard Nossum <vegard.nossum at gmail.com> wrote: > I actually wanted to ask some questions about Nouveau and the NVIDIA > drivers. I was wondering if there would be any point in extending > kmemcheck to track this driver's use of kernel memory. We could quite > easily make a "memory access tracer", which would show all the memory > access patterns of the driver's allocated memory. Not just addresses, > but also offsets into the objects (if it was allocated with slab),...

...seful for diagnostic purposes of > > > Linux > > > > Ok, how do you propose we solve this? > > > > I have asked the question before, and then I had two ideas. Well, the > > first one was actually your idea (so I hear) to solve the same problem for > > kmemcheck. > > - per-cpu page tables > > - instead of single-stepping, emulate the faulting instruction and never > > disarm pages during tracing. (Use and modify code from KVM.) > > > > I don't believe either of these is easy or fast to implement. Given > > some mon...

...mings and makes a race elsewhere a lot more failure prone. Some suggestions: - search kernel mailing lists for CFQ bug reports (since it seems to happen in CFQ code) - try to reproduce it without nouveau, e.g., try an old FB driver - try enabling heavy debugging features in the kernel config, like kmemcheck or kmemleak I'm trying to steer this away from Nouveau first, because it looks very difficult to debug. In the future, please provide full kernel logs from boot, and set attachment type to text/plain. -- Configure bugmail: http://bugs.freedesktop.org/userprefs.cgi?tab=email ------- You are...

...x/dma-mapping.h @@ -5,13 +5,25 @@ #include <linux/string.h> #include <linux/device.h> #include <linux/err.h> -#include <linux/dma-attrs.h> #include <linux/dma-debug.h> #include <linux/dma-direction.h> #include <linux/scatterlist.h> #include <linux/kmemcheck.h> #include <linux/bug.h> +/** + * List of possible attributes associated with a DMA mapping. The semantics + * of each attribute should be defined in Documentation/DMA-attributes.txt. + */ +#define DMA_ATTR_WRITE_BARRIER (1UL << 1) +#define DMA_ATTR_WEAK_ORDERING (1UL <<...

What it is: vhost net is a character device that can be used to reduce the number of system calls involved in virtio networking. Existing virtio net code is used in the guest without modification. There's similarity with vringfd, with some differences and reduced scope - uses eventfd for signalling - structures can be moved around in memory at any time (good for migration, bug work-arounds

What it is: vhost net is a character device that can be used to reduce the number of system calls involved in virtio networking. Existing virtio net code is used in the guest without modification. There's similarity with vringfd, with some differences and reduced scope - uses eventfd for signalling - structures can be moved around in memory at any time (good for migration, bug work-arounds

Hi, This is third approach (complete this time) for replacing struct dma_attrs with unsigned long. The main patch (2/45) doing the change is split into many subpatches for easier review (3-43). They should be squashed together when applying. *Important:* Patchset is *only* build tested on allyesconfigs: ARM, ARM64, i386, x86_64 and powerpc. Please provide reviewes and tests for other