search for: sprinking

On Fri, Oct 20, 2017 at 1:26 AM, Ingo Molnar <mingo at kernel.org> wrote: > > * Thomas Garnier <thgarnie at google.com> wrote: > >> Change the assembly code to use only relative references of symbols for the >> kernel to be PIE compatible. >> >> Position Independent Executable (PIE) support will allow to extended the >> KASLR randomization range

On Fri, Oct 20, 2017 at 1:26 AM, Ingo Molnar <mingo at kernel.org> wrote: > > * Thomas Garnier <thgarnie at google.com> wrote: > >> Change the assembly code to use only relative references of symbols for the >> kernel to be PIE compatible. >> >> Position Independent Executable (PIE) support will allow to extended the >> KASLR randomization range

...tch seems to add extra overhead to the syscall fast-path even when PIE is > > disabled, right? > > It does add extra instructions when one is not possible, I preferred > that over ifdefing but I can change it. So my problem is, this pattern repeats in many other places as well, but sprinking various pieces of assembly code with #ifdefs would be very bad as well. I have no good idea how to solve this. Thanks, Ingo

(OS: Fedora Core 5; dovecot: 1.0 rc7) On a typical UNIX-like OS, the INBOXes are in "/var/spool/mail/" using the user identifier: so user 'fred' has INBOX "/var/spool/mail/fred". We have a well-established different convention which subdivides this, based on the last two digits of the uid: "/var/spool/mail/12/fred" (for fred's uid as something ending

...tio_clear_bit(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT); What is this doing? Basically handling the case where vq is broken? It's kind of ugly to tweak feature bits, most code assumes they never change. Please just return an error to caller instead and handle it there. You can then avoid sprinking the check for the feature bit all over the code. > + > + virtqueue_kick(vq); > +} > + > /* > * While most virtqueues communicate guest-initiated requests to the hypervisor, > * the stats queue operates in reverse. The driver initializes the virtqueue > @@ -316,17 +382...

...tio_clear_bit(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT); What is this doing? Basically handling the case where vq is broken? It's kind of ugly to tweak feature bits, most code assumes they never change. Please just return an error to caller instead and handle it there. You can then avoid sprinking the check for the feature bit all over the code. > + > + virtqueue_kick(vq); > +} > + > /* > * While most virtqueues communicate guest-initiated requests to the hypervisor, > * the stats queue operates in reverse. The driver initializes the virtqueue > @@ -316,17 +382...

Anyone had any thoughts on the item below? If the problem is with my config, I'd like to be guided towards how I might resolve it. If it is a bug in rc7, it would be good to fix it, and I'd be happy to beta-test. -- : David Lee I.T. Service : : Senior Systems Programmer Computer Centre : :

This patch series is separated from the previous "Virtio-balloon Enhancement" series. The new feature, VIRTIO_BALLOON_F_FREE_PAGE_HINT, implemented by this series enables the virtio-balloon driver to report hints of guest free pages to the host. It can be used to accelerate live migration of VMs. Here is an introduction of this usage: Live migration needs to transfer the VM's