Re: [PATCH v1 06/27] x86/entry/64: Adapt assembly for PIE support

2017-10-20 Thread Andy Lutomirski
> On Oct 20, 2017, at 5:20 PM, Ingo Molnar wrote: > > > * Thomas Garnier wrote: > */ - cmpq$.Lentry_SYSCALL_64_after_fastpath_call, (%rsp) + leaq.Lentry_SYSCALL_64_after_fastpath_call(%rip), %r11 + cmpq

Re: [PATCH v1 06/27] x86/entry/64: Adapt assembly for PIE support

2017-10-20 Thread Andy Lutomirski
> On Oct 20, 2017, at 5:20 PM, Ingo Molnar wrote: > > > * Thomas Garnier wrote: > */ - cmpq$.Lentry_SYSCALL_64_after_fastpath_call, (%rsp) + leaq.Lentry_SYSCALL_64_after_fastpath_call(%rip), %r11 + cmpq

Re: [PATCH v1 06/27] x86/entry/64: Adapt assembly for PIE support

2017-10-20 Thread Ingo Molnar
* Thomas Garnier wrote: > >>*/ > >> - cmpq$.Lentry_SYSCALL_64_after_fastpath_call, (%rsp) > >> + leaq.Lentry_SYSCALL_64_after_fastpath_call(%rip), %r11 > >> + cmpq%r11, (%rsp) > >> jne 1f > > This patch seems to add extra overhead

[PATCH v1 3/3] virtio-balloon: stop inflating when OOM occurs

2017-10-20 Thread Wei Wang
This patch forces the cease of the inflating work when OOM occurs. The fundamental idea of memory ballooning is to take out some guest pages when the guest has low memory utilization, so it is sensible to inflate nothing when the guest is already under memory pressure. On the other hand, the

[PATCH v1 2/3] virtio-balloon: deflate up to oom_pages on OOM

2017-10-20 Thread Wei Wang
The current implementation only deflates 256 pages even when a user specifies more than that via the oom_pages module param. This patch enables the deflating of up to oom_pages pages if there are enough inflated pages. Signed-off-by: Wei Wang Cc: Michael S. Tsirkin

[PATCH v1 0/3] Virtio-balloon Improvement

2017-10-20 Thread Wei Wang
This patch series intends to summarize the recent contributions made by Michael S. Tsirkin, Tetsuo Handa, Michal Hocko etc. via reporting and discussing the related deadlock issues on the mailinglist. Please check each patch for details. >From a high-level point of view, this patch series

[PATCH v1 1/3] virtio-balloon: replace the coarse-grained balloon_lock

2017-10-20 Thread Wei Wang
The balloon_lock was used to synchronize the access demand to elements of struct virtio_balloon and its queue operations (please see commit e22504296d). This prevents the concurrent run of the leak_balloon and fill_balloon functions, thereby resulting in a deadlock issue on OOM: fill_balloon:

Re: [PATCH v1 01/27] x86/crypto: Adapt assembly for PIE support

2017-10-20 Thread Ard Biesheuvel
On 20 October 2017 at 09:24, Ingo Molnar wrote: > > * Thomas Garnier 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

Re: [PATCH v1 06/27] x86/entry/64: Adapt assembly for PIE support

2017-10-20 Thread Ingo Molnar
* Thomas Garnier 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 below the -2G memory limit. > >

Re: [PATCH v1 01/27] x86/crypto: Adapt assembly for PIE support

2017-10-20 Thread Ingo Molnar
* Thomas Garnier 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 below the -2G memory limit. > diff