* Re: ppc64le and 32-bit LE userland compatibility
From: Daniel Kolesa @ 2020-06-01 23:26 UTC (permalink / raw)
To: Joseph Myers, Will Springer
Cc: libc-alpha, eery, musl, Palmer Dabbelt via binutils, via libc-dev,
linuxppc-dev
In-Reply-To: <alpine.DEB.2.21.2006012119010.11121@digraph.polyomino.org.uk>
On Mon, Jun 1, 2020, at 23:28, Joseph Myers wrote:
> On Fri, 29 May 2020, Will Springer via Binutils wrote:
>
> > Hey all, a couple of us over in #talos-workstation on freenode have been
> > working on an effort to bring up a Linux PowerPC userland that runs in 32-bit
> > little-endian mode, aka ppcle. As far as we can tell, no ABI has ever been
> > designated for this (unless you count the patchset from a decade ago [1]), so
> > it's pretty much uncharted territory as far as Linux is concerned. We want to
> > sync up with libc and the relevant kernel folks to establish the best path
> > forward.
>
> As a general comment on the glibc side of things, if this is considered
> like a new port, and it probably is, the same principles that apply to new
> ports apply here.
>
> There's a general discussion at
> <https://sourceware.org/glibc/wiki/NewPorts>, although much of that is
> only applicable when adding new CPU architecture support. More specific
> points include that new 32-bit ports should default to 64-bit time and
> file offsets from the start, with no support for 32-bit time or offsets
> (meaning that if you want to use this with some kind of library call
> translation, the library call translation will need to deal with
> corresponding type size conversions). And a new port should not be added
> that uses the IBM long double format. You can use IEEE binary128 long
> double, possibly with an ABI similar to that used on powerpc64le, or can
> use long double = double, but should not support IBM long double, and
> preferably should only have one long double format rather than using the
> glibc support for building with different options resulting in functions
> for different long double formats being called.
Are you sure this would be a new port? Glibc already works in this combination, as it seems to me it'd be best if it was just a variant of the existing 32-bit PowerPC port, sharing most conventions besides endianness with the BE port.
128-bit IEEE long double would not work, since that relies on VSX being present (gcc will explicitly complain if it's not). I'd be all for using 64-bit long double, though (musl already does, on all ppc ports).
While we're at long double, I'd actually be interested in transitioning the existing big endian ports in Void (64-bit and 32-bit, neither has VSX baseline requirement in my case) to using 64-bit long double, abandoning the IBM format altogether (little endian will transition to 128-bit IEEE long double once it's ready on your side, as that assumes POWER8 baseline which includes VSX).
What would be the best way for me to proceed with that? I actually experimented with this, using the old glibc compat symbols from pre-ibm128 times, and I mostly had it working, except I haven't managed to find a way to switch the default symbols to 64-bit ones, which is problematic as linking everything against nldbl_nonshared is fragile and potentially quirky (breaks dlsym, function pointer equality across libraries, etc).
There is also one more thing while we're at this. The 64-bit big endian Void port uses the ELFv2 ABI, even on glibc. This is not officially supported on glibc as far as I can tell, but it does work out of box, without any patching (things in general match little endian then, i.e. ld64.so.2 etc, but they're big endian). Is there any chance of making that support official?
>
> --
> Joseph S. Myers
> joseph@codesourcery.com
>
Daniel
^ permalink raw reply
* Re: [musl] Re: ppc64le and 32-bit LE userland compatibility
From: Rich Felker @ 2020-06-01 21:36 UTC (permalink / raw)
To: Joseph Myers
Cc: libc-alpha, eery, daniel, musl, Will Springer, binutils, libc-dev,
linuxppc-dev
In-Reply-To: <alpine.DEB.2.21.2006012119010.11121@digraph.polyomino.org.uk>
On Mon, Jun 01, 2020 at 09:28:25PM +0000, Joseph Myers wrote:
> On Fri, 29 May 2020, Will Springer via Binutils wrote:
>
> > Hey all, a couple of us over in #talos-workstation on freenode have been
> > working on an effort to bring up a Linux PowerPC userland that runs in 32-bit
> > little-endian mode, aka ppcle. As far as we can tell, no ABI has ever been
> > designated for this (unless you count the patchset from a decade ago [1]), so
> > it's pretty much uncharted territory as far as Linux is concerned. We want to
> > sync up with libc and the relevant kernel folks to establish the best path
> > forward.
>
> As a general comment on the glibc side of things, if this is considered
> like a new port, and it probably is, the same principles that apply to new
> ports apply here.
>
> There's a general discussion at
> <https://sourceware.org/glibc/wiki/NewPorts>, although much of that is
> only applicable when adding new CPU architecture support. More specific
> points include that new 32-bit ports should default to 64-bit time and
> file offsets from the start, with no support for 32-bit time or offsets
> (meaning that if you want to use this with some kind of library call
> translation, the library call translation will need to deal with
> corresponding type size conversions). And a new port should not be added
> that uses the IBM long double format. You can use IEEE binary128 long
> double, possibly with an ABI similar to that used on powerpc64le, or can
> use long double = double, but should not support IBM long double, and
> preferably should only have one long double format rather than using the
> glibc support for building with different options resulting in functions
> for different long double formats being called.
Thanks, these are great points, and the same applies for musl I think.
We always have 64-bit off_t anyway, but new ports should have 64-bit
time_t to begin with rather than defining _REDIR_TIME64.
It's a little bit complicated by the fact that powerpcle would be a
"subarch" for powerpc, and we don't yet have any like that where the
subarchs' time64 statuses differ, but it doesn't look like that should
be hard to do. The arch-specific alltypes.h.in already has access to
endianness knowledge. src/ldso/powerpc/dlsym_time64.S would also need
added preprocessor conditionals.
Exemption from this would be open to discussion if there are existing
non-upstream users of powerpcle musl that otherwise complies with ABI
policy except for time64, but I'm not aware of any that aren't
experimental.
Rich
^ permalink raw reply
* Re: ppc64le and 32-bit LE userland compatibility
From: Joseph Myers @ 2020-06-01 21:28 UTC (permalink / raw)
To: Will Springer
Cc: libc-alpha, eery, daniel, musl, binutils, libc-dev, linuxppc-dev
In-Reply-To: <2047231.C4sosBPzcN@sheen>
On Fri, 29 May 2020, Will Springer via Binutils wrote:
> Hey all, a couple of us over in #talos-workstation on freenode have been
> working on an effort to bring up a Linux PowerPC userland that runs in 32-bit
> little-endian mode, aka ppcle. As far as we can tell, no ABI has ever been
> designated for this (unless you count the patchset from a decade ago [1]), so
> it's pretty much uncharted territory as far as Linux is concerned. We want to
> sync up with libc and the relevant kernel folks to establish the best path
> forward.
As a general comment on the glibc side of things, if this is considered
like a new port, and it probably is, the same principles that apply to new
ports apply here.
There's a general discussion at
<https://sourceware.org/glibc/wiki/NewPorts>, although much of that is
only applicable when adding new CPU architecture support. More specific
points include that new 32-bit ports should default to 64-bit time and
file offsets from the start, with no support for 32-bit time or offsets
(meaning that if you want to use this with some kind of library call
translation, the library call translation will need to deal with
corresponding type size conversions). And a new port should not be added
that uses the IBM long double format. You can use IEEE binary128 long
double, possibly with an ABI similar to that used on powerpc64le, or can
use long double = double, but should not support IBM long double, and
preferably should only have one long double format rather than using the
glibc support for building with different options resulting in functions
for different long double formats being called.
--
Joseph S. Myers
joseph@codesourcery.com
^ permalink raw reply
* Re: [PATCH v1 3/4] KVM: PPC: Book3S HV: migrate remaining normal-GFNs to secure-GFNs in H_SVM_INIT_DONE
From: Ram Pai @ 2020-06-01 19:05 UTC (permalink / raw)
To: Bharata B Rao
Cc: ldufour, cclaudio, kvm-ppc, aneesh.kumar, sukadev, linuxppc-dev,
bauerman, david
In-Reply-To: <20200601115518.GA31382@in.ibm.com>
On Mon, Jun 01, 2020 at 05:25:18PM +0530, Bharata B Rao wrote:
> On Sat, May 30, 2020 at 07:27:50PM -0700, Ram Pai wrote:
> > H_SVM_INIT_DONE incorrectly assumes that the Ultravisor has explicitly
> > called H_SVM_PAGE_IN for all secure pages.
>
> I don't think that is quite true. HV doesn't assume anything about
> secure pages by itself.
Yes. Currently, it does not assume anything about secure pages. But I am
proposing that it should consider all pages (except the shared pages) as
secure pages, when H_SVM_INIT_DONE is called.
In other words, HV should treat all pages; except shared pages, as
secure pages once H_SVM_INIT_DONE is called. And this includes pages
added subsequently through memory hotplug.
Yes. the Ultravisor can explicitly request the HV to move the pages
individually. But that will slow down the transition too significantly.
It takes above 20min to transition them, for a SVM of size 100G.
With this proposed enhancement, the switch completes in a few seconds.
>
> > These GFNs continue to be
> > normal GFNs associated with normal PFNs; when infact, these GFNs should
> > have been secure GFNs associated with device PFNs.
>
> Transition to secure state is driven by SVM/UV and HV just responds to
> hcalls by issuing appropriate uvcalls. SVM/UV is in the best position to
> determine the required pages that need to be moved into secure side.
> HV just responds to it and tracks such pages as device private pages.
>
> If SVM/UV doesn't get in all the pages to secure side by the time
> of H_SVM_INIT_DONE, the remaining pages are just normal (shared or
> otherwise) pages as far as HV is concerned. Why should HV assume that
> SVM/UV didn't ask for a few pages and hence push those pages during
> H_SVM_INIT_DONE?
By definition, SVM is a VM backed by secure pages.
Hence all pages(except shared) must turn secure when a VM switches to SVM.
UV is interested in only a certain pages for the VM, which it will
request explicitly through H_SVM_PAGE_IN. All other pages, need not
be paged-in through UV_PAGE_IN. They just need to be switched to
device-pages.
>
> I think UV should drive the movement of pages into secure side both
> of boot-time SVM memory and hot-plugged memory. HV does memslot
> registration uvcall when new memory is plugged in, UV should explicitly
> get the required pages in at that time instead of expecting HV to drive
> the same.
>
> > +static int uv_migrate_mem_slot(struct kvm *kvm,
> > + const struct kvm_memory_slot *memslot)
> > +{
> > + unsigned long gfn = memslot->base_gfn;
> > + unsigned long end;
> > + bool downgrade = false;
> > + struct vm_area_struct *vma;
> > + int i, ret = 0;
> > + unsigned long start = gfn_to_hva(kvm, gfn);
> > +
> > + if (kvm_is_error_hva(start))
> > + return H_STATE;
> > +
> > + end = start + (memslot->npages << PAGE_SHIFT);
> > +
> > + down_write(&kvm->mm->mmap_sem);
> > +
> > + mutex_lock(&kvm->arch.uvmem_lock);
> > + vma = find_vma_intersection(kvm->mm, start, end);
> > + if (!vma || vma->vm_start > start || vma->vm_end < end) {
> > + ret = H_STATE;
> > + goto out_unlock;
> > + }
> > +
> > + ret = ksm_madvise(vma, vma->vm_start, vma->vm_end,
> > + MADV_UNMERGEABLE, &vma->vm_flags);
> > + downgrade_write(&kvm->mm->mmap_sem);
> > + downgrade = true;
> > + if (ret) {
> > + ret = H_STATE;
> > + goto out_unlock;
> > + }
> > +
> > + for (i = 0; i < memslot->npages; i++, ++gfn) {
> > + /* skip paged-in pages and shared pages */
> > + if (kvmppc_gfn_is_uvmem_pfn(gfn, kvm, NULL) ||
> > + kvmppc_gfn_is_uvmem_shared(gfn, kvm))
> > + continue;
> > +
> > + start = gfn_to_hva(kvm, gfn);
> > + end = start + (1UL << PAGE_SHIFT);
> > + ret = kvmppc_svm_migrate_page(vma, start, end,
> > + (gfn << PAGE_SHIFT), kvm, PAGE_SHIFT, false);
> > +
> > + if (ret)
> > + goto out_unlock;
> > + }
>
> Is there a guarantee that the vma you got for the start address remains
> valid for all the addresses till end in a memslot? If not, you should
> re-get the vma for the current address in each iteration I suppose.
mm->mmap_sem is the semaphore that guards the vma. right? If that
semaphore is held, can the vma change?
Thanks for your comments,
RP
^ permalink raw reply
* Re: [RFC PATCH 1/2] libnvdimm: Add prctl control for disabling synchronous fault support.
From: Jan Kara @ 2020-06-01 14:56 UTC (permalink / raw)
To: Aneesh Kumar K.V
Cc: Jan Kara, linux-nvdimm, jack, Jeff Moyer, oohall, dan.j.williams,
Michal Suchánek, linuxppc-dev
In-Reply-To: <2bf026cc-2ed0-70b6-bf99-ecfd0fa3dac4@linux.ibm.com>
On Mon 01-06-20 17:31:50, Aneesh Kumar K.V wrote:
> On 6/1/20 3:39 PM, Jan Kara wrote:
> > On Fri 29-05-20 16:25:35, Aneesh Kumar K.V wrote:
> > > On 5/29/20 3:22 PM, Jan Kara wrote:
> > > > On Fri 29-05-20 15:07:31, Aneesh Kumar K.V wrote:
> > > > > Thanks Michal. I also missed Jeff in this email thread.
> > > >
> > > > And I think you'll also need some of the sched maintainers for the prctl
> > > > bits...
> > > >
> > > > > On 5/29/20 3:03 PM, Michal Suchánek wrote:
> > > > > > Adding Jan
> > > > > >
> > > > > > On Fri, May 29, 2020 at 11:11:39AM +0530, Aneesh Kumar K.V wrote:
> > > > > > > With POWER10, architecture is adding new pmem flush and sync instructions.
> > > > > > > The kernel should prevent the usage of MAP_SYNC if applications are not using
> > > > > > > the new instructions on newer hardware.
> > > > > > >
> > > > > > > This patch adds a prctl option MAP_SYNC_ENABLE that can be used to enable
> > > > > > > the usage of MAP_SYNC. The kernel config option is added to allow the user
> > > > > > > to control whether MAP_SYNC should be enabled by default or not.
> > > > > > >
> > > > > > > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> > > > ...
> > > > > > > diff --git a/kernel/fork.c b/kernel/fork.c
> > > > > > > index 8c700f881d92..d5a9a363e81e 100644
> > > > > > > --- a/kernel/fork.c
> > > > > > > +++ b/kernel/fork.c
> > > > > > > @@ -963,6 +963,12 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock);
> > > > > > > static unsigned long default_dump_filter = MMF_DUMP_FILTER_DEFAULT;
> > > > > > > +#ifdef CONFIG_ARCH_MAP_SYNC_DISABLE
> > > > > > > +unsigned long default_map_sync_mask = MMF_DISABLE_MAP_SYNC_MASK;
> > > > > > > +#else
> > > > > > > +unsigned long default_map_sync_mask = 0;
> > > > > > > +#endif
> > > > > > > +
> > > >
> > > > I'm not sure CONFIG is really the right approach here. For a distro that would
> > > > basically mean to disable MAP_SYNC for all PPC kernels unless application
> > > > explicitly uses the right prctl. Shouldn't we rather initialize
> > > > default_map_sync_mask on boot based on whether the CPU we run on requires
> > > > new flush instructions or not? Otherwise the patch looks sensible.
> > > >
> > >
> > > yes that is correct. We ideally want to deny MAP_SYNC only w.r.t POWER10.
> > > But on a virtualized platform there is no easy way to detect that. We could
> > > ideally hook this into the nvdimm driver where we look at the new compat
> > > string ibm,persistent-memory-v2 and then disable MAP_SYNC
> > > if we find a device with the specific value.
> >
> > Hum, couldn't we set some flag for nvdimm devices with
> > "ibm,persistent-memory-v2" property and then check it during mmap(2) time
> > and when the device has this propery and the mmap(2) caller doesn't have
> > the prctl set, we'd disallow MAP_SYNC? That should make things mostly
> > seamless, shouldn't it? Only apps that want to use MAP_SYNC on these
> > devices would need to use prctl(MMF_DISABLE_MAP_SYNC, 0) but then these
> > applications need to be aware of new instructions so this isn't that much
> > additional burden...
>
> I am not sure application would want to add that much details/knowledge
> about a platform in their code. I was expecting application to do
>
> #ifdef __ppc64__
> prctl(MAP_SYNC_ENABLE, 1, 0, 0, 0));
> #endif
> a = mmap(NULL, PAGE_SIZE, PROT_READ|PROT_WRITE,
> MAP_SHARED_VALIDATE | MAP_SYNC, fd, 0);
>
>
> For that code all the complexity that we add w.r.t ibm,persistent-memory-v2
> is not useful. Do you see a value in making all these device specific rather
> than a conditional on __ppc64__?
Yes, from the application POV the code would look like this plus the
application would use instructions appropriate for POWER10 for flushing
caches...
Honza
--
Jan Kara <jack@suse.com>
SUSE Labs, CR
^ permalink raw reply
* Re: [PATCH v8 2/5] seq_buf: Export seq_buf_printf
From: Vaibhav Jain @ 2020-06-01 14:46 UTC (permalink / raw)
To: Steven Rostedt
Cc: Santosh Sivaraj, Ira Weiny, linux-nvdimm, Aneesh Kumar K . V,
Cezary Rojewski, Piotr Maziarz, linux-kernel, Christoph Hellwig,
Oliver O'Halloran, Borislav Petkov, Dan Williams,
linuxppc-dev
In-Reply-To: <20200601094842.3cd0cab6@gandalf.local.home>
Steven Rostedt <rostedt@goodmis.org> writes:
> On Mon, 01 Jun 2020 17:31:31 +0530
> Vaibhav Jain <vaibhav@linux.ibm.com> wrote:
>
>> Hi Christoph and Steven,
>>
>> Have addressed your review comment to update the patch description and
>> title for this patch. Can you please provide your ack to this patch.
>>
>>
>
> I thought I already did, but it appears it was a reply to a private email
> you sent to me. I didn't realize it was off list.
>
> Anyway:
>
> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Thanks Steven,
Had added your ack to Resend-v7 of this patch at [1] on which Christoph
Hellwig requested an update of patch title. Hence needed your re-ack for
this version of the patch
[1] : https://lore.kernel.org/linux-nvdimm/20200519190058.257981-3-vaibhav@linux.ibm.com/
>
> -- Steve
Cheers
~ Vaibhav
^ permalink raw reply
* Re: [PATCH v8 2/5] seq_buf: Export seq_buf_printf
From: Steven Rostedt @ 2020-06-01 13:48 UTC (permalink / raw)
To: Vaibhav Jain
Cc: Santosh Sivaraj, linux-nvdimm, Aneesh Kumar K . V, linuxppc-dev,
Cezary Rojewski, Piotr Maziarz, Christoph Hellwig,
Oliver O'Halloran, Borislav Petkov, Dan Williams, Ira Weiny,
linux-kernel
In-Reply-To: <87367f9eqs.fsf@linux.ibm.com>
On Mon, 01 Jun 2020 17:31:31 +0530
Vaibhav Jain <vaibhav@linux.ibm.com> wrote:
> Hi Christoph and Steven,
>
> Have addressed your review comment to update the patch description and
> title for this patch. Can you please provide your ack to this patch.
>
>
I thought I already did, but it appears it was a reply to a private email
you sent to me. I didn't realize it was off list.
Anyway:
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
-- Steve
^ permalink raw reply
* [powerpc:next-test 177/198] arch/powerpc/kernel/rtas.c:519:9: error: 'local_paca' undeclared; did you mean 'local_inc'?
From: kbuild test robot @ 2020-06-01 12:45 UTC (permalink / raw)
To: Leonardo, Bras,; +Cc: linuxppc-dev, kbuild-all
[-- Attachment #1: Type: text/plain, Size: 3066 bytes --]
tree: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next-test
head: e376ca093587eafd840bb0f9df04090e2a54249c
commit: a3871a8b701613da2a13d6d1c523d0bb29ba62de [177/198] powerpc/rtas: Implement reentrant rtas call
config: powerpc-chrp32_defconfig (attached as .config)
compiler: powerpc-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
git checkout a3871a8b701613da2a13d6d1c523d0bb29ba62de
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc
If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>
All errors (new ones prefixed by >>, old ones prefixed by <<):
arch/powerpc/kernel/rtas.c: In function 'rtas_call_reentrant':
>> arch/powerpc/kernel/rtas.c:519:9: error: 'local_paca' undeclared (first use in this function); did you mean 'local_inc'?
519 | args = local_paca->rtas_args_reentrant;
| ^~~~~~~~~~
| local_inc
arch/powerpc/kernel/rtas.c:519:9: note: each undeclared identifier is reported only once for each function it appears in
vim +519 arch/powerpc/kernel/rtas.c
486
487 /**
488 * rtas_call_reentrant() - Used for reentrant rtas calls
489 * @token: Token for desired reentrant RTAS call
490 * @nargs: Number of Input Parameters
491 * @nret: Number of Output Parameters
492 * @outputs: Array of outputs
493 * @...: Inputs for desired RTAS call
494 *
495 * According to LoPAR documentation, only "ibm,int-on", "ibm,int-off",
496 * "ibm,get-xive" and "ibm,set-xive" are currently reentrant.
497 * Reentrant calls need their own rtas_args buffer, so not using rtas.args, but
498 * PACA one instead.
499 *
500 * Return: -1 on error,
501 * First output value of RTAS call if (nret > 0),
502 * 0 otherwise,
503 */
504
505 int rtas_call_reentrant(int token, int nargs, int nret, int *outputs, ...)
506 {
507 va_list list;
508 struct rtas_args *args;
509 unsigned long flags;
510 int i, ret = 0;
511
512 if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)
513 return -1;
514
515 local_irq_save(flags);
516 preempt_disable();
517
518 /* We use the per-cpu (PACA) rtas args buffer */
> 519 args = local_paca->rtas_args_reentrant;
520
521 va_start(list, outputs);
522 va_rtas_call_unlocked(args, token, nargs, nret, list);
523 va_end(list);
524
525 if (nret > 1 && outputs)
526 for (i = 0; i < nret - 1; ++i)
527 outputs[i] = be32_to_cpu(args->rets[i + 1]);
528
529 if (nret > 0)
530 ret = be32_to_cpu(args->rets[0]);
531
532 local_irq_restore(flags);
533 preempt_enable();
534
535 return ret;
536 }
537
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 18831 bytes --]
^ permalink raw reply
* Re: [RFC PATCH 1/2] libnvdimm: Add prctl control for disabling synchronous fault support.
From: Aneesh Kumar K.V @ 2020-06-01 12:20 UTC (permalink / raw)
To: Michal Suchánek
Cc: Jan Kara, linux-nvdimm, jack, Jeff Moyer, oohall, dan.j.williams,
linuxppc-dev
In-Reply-To: <20200601120705.GQ25173@kitsune.suse.cz>
On 6/1/20 5:37 PM, Michal Suchánek wrote:
> On Mon, Jun 01, 2020 at 05:31:50PM +0530, Aneesh Kumar K.V wrote:
>> On 6/1/20 3:39 PM, Jan Kara wrote:
>>> On Fri 29-05-20 16:25:35, Aneesh Kumar K.V wrote:
>>>> On 5/29/20 3:22 PM, Jan Kara wrote:
>>>>> On Fri 29-05-20 15:07:31, Aneesh Kumar K.V wrote:
>>>>>> Thanks Michal. I also missed Jeff in this email thread.
>>>>>
>>>>> And I think you'll also need some of the sched maintainers for the prctl
>>>>> bits...
>>>>>
>>>>>> On 5/29/20 3:03 PM, Michal Suchánek wrote:
>>>>>>> Adding Jan
>>>>>>>
>>>>>>> On Fri, May 29, 2020 at 11:11:39AM +0530, Aneesh Kumar K.V wrote:
>>>>>>>> With POWER10, architecture is adding new pmem flush and sync instructions.
>>>>>>>> The kernel should prevent the usage of MAP_SYNC if applications are not using
>>>>>>>> the new instructions on newer hardware.
>>>>>>>>
>>>>>>>> This patch adds a prctl option MAP_SYNC_ENABLE that can be used to enable
>>>>>>>> the usage of MAP_SYNC. The kernel config option is added to allow the user
>>>>>>>> to control whether MAP_SYNC should be enabled by default or not.
>>>>>>>>
>>>>>>>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
>>>>> ...
>>>>>>>> diff --git a/kernel/fork.c b/kernel/fork.c
>>>>>>>> index 8c700f881d92..d5a9a363e81e 100644
>>>>>>>> --- a/kernel/fork.c
>>>>>>>> +++ b/kernel/fork.c
>>>>>>>> @@ -963,6 +963,12 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock);
>>>>>>>> static unsigned long default_dump_filter = MMF_DUMP_FILTER_DEFAULT;
>>>>>>>> +#ifdef CONFIG_ARCH_MAP_SYNC_DISABLE
>>>>>>>> +unsigned long default_map_sync_mask = MMF_DISABLE_MAP_SYNC_MASK;
>>>>>>>> +#else
>>>>>>>> +unsigned long default_map_sync_mask = 0;
>>>>>>>> +#endif
>>>>>>>> +
>>>>>
>>>>> I'm not sure CONFIG is really the right approach here. For a distro that would
>>>>> basically mean to disable MAP_SYNC for all PPC kernels unless application
>>>>> explicitly uses the right prctl. Shouldn't we rather initialize
>>>>> default_map_sync_mask on boot based on whether the CPU we run on requires
>>>>> new flush instructions or not? Otherwise the patch looks sensible.
>>>>>
>>>>
>>>> yes that is correct. We ideally want to deny MAP_SYNC only w.r.t POWER10.
>>>> But on a virtualized platform there is no easy way to detect that. We could
>>>> ideally hook this into the nvdimm driver where we look at the new compat
>>>> string ibm,persistent-memory-v2 and then disable MAP_SYNC
>>>> if we find a device with the specific value.
>>>
>>> Hum, couldn't we set some flag for nvdimm devices with
>>> "ibm,persistent-memory-v2" property and then check it during mmap(2) time
>>> and when the device has this propery and the mmap(2) caller doesn't have
>>> the prctl set, we'd disallow MAP_SYNC? That should make things mostly
>>> seamless, shouldn't it? Only apps that want to use MAP_SYNC on these
>>> devices would need to use prctl(MMF_DISABLE_MAP_SYNC, 0) but then these
>>> applications need to be aware of new instructions so this isn't that much
>>> additional burden...
>>
>> I am not sure application would want to add that much details/knowledge
>> about a platform in their code. I was expecting application to do
>>
>> #ifdef __ppc64__
>> prctl(MAP_SYNC_ENABLE, 1, 0, 0, 0));
>> #endif
>> a = mmap(NULL, PAGE_SIZE, PROT_READ|PROT_WRITE,
>> MAP_SHARED_VALIDATE | MAP_SYNC, fd, 0);
>>
>>
>> For that code all the complexity that we add w.r.t ibm,persistent-memory-v2
>> is not useful. Do you see a value in making all these device specific rather
>> than a conditional on __ppc64__?
> If the vpmem devices continue to work with the old instruction on
> POWER10 then it makes sense to make this per-device.
vPMEM doesn't have write_cache and hence it is synchronous even without
using any specific flush instruction. The question is do we want to have
different programming steps when running on vPMEM vs a persistent PMEM
device on ppc64.
I will work on the device specific ENABLE flag and then we can compare
the kernel complexity against the added benefit.
-aneesh
^ permalink raw reply
* Re: [RFC PATCH 1/2] libnvdimm: Add prctl control for disabling synchronous fault support.
From: Michal Suchánek @ 2020-06-01 12:07 UTC (permalink / raw)
To: Aneesh Kumar K.V
Cc: Jan Kara, linux-nvdimm, jack, Jeff Moyer, oohall, dan.j.williams,
linuxppc-dev
In-Reply-To: <2bf026cc-2ed0-70b6-bf99-ecfd0fa3dac4@linux.ibm.com>
On Mon, Jun 01, 2020 at 05:31:50PM +0530, Aneesh Kumar K.V wrote:
> On 6/1/20 3:39 PM, Jan Kara wrote:
> > On Fri 29-05-20 16:25:35, Aneesh Kumar K.V wrote:
> > > On 5/29/20 3:22 PM, Jan Kara wrote:
> > > > On Fri 29-05-20 15:07:31, Aneesh Kumar K.V wrote:
> > > > > Thanks Michal. I also missed Jeff in this email thread.
> > > >
> > > > And I think you'll also need some of the sched maintainers for the prctl
> > > > bits...
> > > >
> > > > > On 5/29/20 3:03 PM, Michal Suchánek wrote:
> > > > > > Adding Jan
> > > > > >
> > > > > > On Fri, May 29, 2020 at 11:11:39AM +0530, Aneesh Kumar K.V wrote:
> > > > > > > With POWER10, architecture is adding new pmem flush and sync instructions.
> > > > > > > The kernel should prevent the usage of MAP_SYNC if applications are not using
> > > > > > > the new instructions on newer hardware.
> > > > > > >
> > > > > > > This patch adds a prctl option MAP_SYNC_ENABLE that can be used to enable
> > > > > > > the usage of MAP_SYNC. The kernel config option is added to allow the user
> > > > > > > to control whether MAP_SYNC should be enabled by default or not.
> > > > > > >
> > > > > > > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> > > > ...
> > > > > > > diff --git a/kernel/fork.c b/kernel/fork.c
> > > > > > > index 8c700f881d92..d5a9a363e81e 100644
> > > > > > > --- a/kernel/fork.c
> > > > > > > +++ b/kernel/fork.c
> > > > > > > @@ -963,6 +963,12 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock);
> > > > > > > static unsigned long default_dump_filter = MMF_DUMP_FILTER_DEFAULT;
> > > > > > > +#ifdef CONFIG_ARCH_MAP_SYNC_DISABLE
> > > > > > > +unsigned long default_map_sync_mask = MMF_DISABLE_MAP_SYNC_MASK;
> > > > > > > +#else
> > > > > > > +unsigned long default_map_sync_mask = 0;
> > > > > > > +#endif
> > > > > > > +
> > > >
> > > > I'm not sure CONFIG is really the right approach here. For a distro that would
> > > > basically mean to disable MAP_SYNC for all PPC kernels unless application
> > > > explicitly uses the right prctl. Shouldn't we rather initialize
> > > > default_map_sync_mask on boot based on whether the CPU we run on requires
> > > > new flush instructions or not? Otherwise the patch looks sensible.
> > > >
> > >
> > > yes that is correct. We ideally want to deny MAP_SYNC only w.r.t POWER10.
> > > But on a virtualized platform there is no easy way to detect that. We could
> > > ideally hook this into the nvdimm driver where we look at the new compat
> > > string ibm,persistent-memory-v2 and then disable MAP_SYNC
> > > if we find a device with the specific value.
> >
> > Hum, couldn't we set some flag for nvdimm devices with
> > "ibm,persistent-memory-v2" property and then check it during mmap(2) time
> > and when the device has this propery and the mmap(2) caller doesn't have
> > the prctl set, we'd disallow MAP_SYNC? That should make things mostly
> > seamless, shouldn't it? Only apps that want to use MAP_SYNC on these
> > devices would need to use prctl(MMF_DISABLE_MAP_SYNC, 0) but then these
> > applications need to be aware of new instructions so this isn't that much
> > additional burden...
>
> I am not sure application would want to add that much details/knowledge
> about a platform in their code. I was expecting application to do
>
> #ifdef __ppc64__
> prctl(MAP_SYNC_ENABLE, 1, 0, 0, 0));
> #endif
> a = mmap(NULL, PAGE_SIZE, PROT_READ|PROT_WRITE,
> MAP_SHARED_VALIDATE | MAP_SYNC, fd, 0);
>
>
> For that code all the complexity that we add w.r.t ibm,persistent-memory-v2
> is not useful. Do you see a value in making all these device specific rather
> than a conditional on __ppc64__?
If the vpmem devices continue to work with the old instruction on
POWER10 then it makes sense to make this per-device.
Also adding a message to kernel log in case the application does not do
the prctl would be helful for people migrating old code to POWER10.
Thanks
Michal
^ permalink raw reply
* Re: [PATCH v8 2/5] seq_buf: Export seq_buf_printf
From: Vaibhav Jain @ 2020-06-01 12:01 UTC (permalink / raw)
To: Christoph Hellwig, Steven Rostedt
Cc: Santosh Sivaraj, linux-nvdimm, Aneesh Kumar K . V, linuxppc-dev,
Cezary Rojewski, Steven Rostedt, Piotr Maziarz, Christoph Hellwig,
Oliver O'Halloran, Borislav Petkov, Dan Williams, Ira Weiny,
linux-kernel
In-Reply-To: <20200527041244.37821-3-vaibhav@linux.ibm.com>
Hi Christoph and Steven,
Have addressed your review comment to update the patch description and
title for this patch. Can you please provide your ack to this patch.
Thanks,
~ Vaibhav
Vaibhav Jain <vaibhav@linux.ibm.com> writes:
> 'seq_buf' provides a very useful abstraction for writing to a string
> buffer without needing to worry about it over-flowing. However even
> though the API has been stable for couple of years now its still not
> exported to kernel loadable modules limiting its usage.
>
> Hence this patch proposes update to 'seq_buf.c' to mark
> seq_buf_printf() which is part of the seq_buf API to be exported to
> kernel loadable GPL modules. This symbol will be used in later parts
> of this patch-set to simplify content creation for a sysfs attribute.
>
> Cc: Piotr Maziarz <piotrx.maziarz@linux.intel.com>
> Cc: Cezary Rojewski <cezary.rojewski@intel.com>
> Cc: Christoph Hellwig <hch@infradead.org>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Borislav Petkov <bp@alien8.de>
> Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
> ---
> Changelog:
>
> v7..v8:
> * Updated the patch title [ Christoph Hellwig ]
> * Updated patch description to replace confusing term 'external kernel
> modules' to 'kernel lodable modules'.
>
> Resend:
> * Added ack from Steven Rostedt
>
> v6..v7:
> * New patch in the series
> ---
> lib/seq_buf.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/lib/seq_buf.c b/lib/seq_buf.c
> index 4e865d42ab03..707453f5d58e 100644
> --- a/lib/seq_buf.c
> +++ b/lib/seq_buf.c
> @@ -91,6 +91,7 @@ int seq_buf_printf(struct seq_buf *s, const char *fmt, ...)
>
> return ret;
> }
> +EXPORT_SYMBOL_GPL(seq_buf_printf);
>
> #ifdef CONFIG_BINARY_PRINTF
> /**
> --
> 2.26.2
>
--
^ permalink raw reply
* Re: [RFC PATCH 1/2] libnvdimm: Add prctl control for disabling synchronous fault support.
From: Aneesh Kumar K.V @ 2020-06-01 12:01 UTC (permalink / raw)
To: Jan Kara
Cc: linux-nvdimm, jack, Jeff Moyer, oohall, dan.j.williams,
Michal Suchánek, linuxppc-dev
In-Reply-To: <20200601100925.GC3960@quack2.suse.cz>
On 6/1/20 3:39 PM, Jan Kara wrote:
> On Fri 29-05-20 16:25:35, Aneesh Kumar K.V wrote:
>> On 5/29/20 3:22 PM, Jan Kara wrote:
>>> On Fri 29-05-20 15:07:31, Aneesh Kumar K.V wrote:
>>>> Thanks Michal. I also missed Jeff in this email thread.
>>>
>>> And I think you'll also need some of the sched maintainers for the prctl
>>> bits...
>>>
>>>> On 5/29/20 3:03 PM, Michal Suchánek wrote:
>>>>> Adding Jan
>>>>>
>>>>> On Fri, May 29, 2020 at 11:11:39AM +0530, Aneesh Kumar K.V wrote:
>>>>>> With POWER10, architecture is adding new pmem flush and sync instructions.
>>>>>> The kernel should prevent the usage of MAP_SYNC if applications are not using
>>>>>> the new instructions on newer hardware.
>>>>>>
>>>>>> This patch adds a prctl option MAP_SYNC_ENABLE that can be used to enable
>>>>>> the usage of MAP_SYNC. The kernel config option is added to allow the user
>>>>>> to control whether MAP_SYNC should be enabled by default or not.
>>>>>>
>>>>>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
>>> ...
>>>>>> diff --git a/kernel/fork.c b/kernel/fork.c
>>>>>> index 8c700f881d92..d5a9a363e81e 100644
>>>>>> --- a/kernel/fork.c
>>>>>> +++ b/kernel/fork.c
>>>>>> @@ -963,6 +963,12 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock);
>>>>>> static unsigned long default_dump_filter = MMF_DUMP_FILTER_DEFAULT;
>>>>>> +#ifdef CONFIG_ARCH_MAP_SYNC_DISABLE
>>>>>> +unsigned long default_map_sync_mask = MMF_DISABLE_MAP_SYNC_MASK;
>>>>>> +#else
>>>>>> +unsigned long default_map_sync_mask = 0;
>>>>>> +#endif
>>>>>> +
>>>
>>> I'm not sure CONFIG is really the right approach here. For a distro that would
>>> basically mean to disable MAP_SYNC for all PPC kernels unless application
>>> explicitly uses the right prctl. Shouldn't we rather initialize
>>> default_map_sync_mask on boot based on whether the CPU we run on requires
>>> new flush instructions or not? Otherwise the patch looks sensible.
>>>
>>
>> yes that is correct. We ideally want to deny MAP_SYNC only w.r.t POWER10.
>> But on a virtualized platform there is no easy way to detect that. We could
>> ideally hook this into the nvdimm driver where we look at the new compat
>> string ibm,persistent-memory-v2 and then disable MAP_SYNC
>> if we find a device with the specific value.
>
> Hum, couldn't we set some flag for nvdimm devices with
> "ibm,persistent-memory-v2" property and then check it during mmap(2) time
> and when the device has this propery and the mmap(2) caller doesn't have
> the prctl set, we'd disallow MAP_SYNC? That should make things mostly
> seamless, shouldn't it? Only apps that want to use MAP_SYNC on these
> devices would need to use prctl(MMF_DISABLE_MAP_SYNC, 0) but then these
> applications need to be aware of new instructions so this isn't that much
> additional burden...
I am not sure application would want to add that much details/knowledge
about a platform in their code. I was expecting application to do
#ifdef __ppc64__
prctl(MAP_SYNC_ENABLE, 1, 0, 0, 0));
#endif
a = mmap(NULL, PAGE_SIZE, PROT_READ|PROT_WRITE,
MAP_SHARED_VALIDATE | MAP_SYNC, fd, 0);
For that code all the complexity that we add w.r.t
ibm,persistent-memory-v2 is not useful. Do you see a value in making all
these device specific rather than a conditional on __ppc64__?
>
>> With that I am wondering should we even have this patch? Can we expect
>> userspace get updated to use new instruction?.
>>
>> With ppc64 we never had a real persistent memory device available for end
>> user to try. The available persistent memory stack was using vPMEM which was
>> presented as a volatile memory region for which there is no need to use any
>> of the flush instructions. We could safely assume that as we get
>> applications certified/verified for working with pmem device on ppc64, they
>> would all be using the new instructions?
>
> This is a bit of a gamble... I don't have too much trust in certification /
> verification because only the "big players" may do powerfail testing
> throughout enough that they'd uncover these problems. So the question
> really is: How many apps are out there using MAP_SYNC on ppc64? Hopefully
> not many given the HW didn't ship yet as you wrote but I have no real clue.
> Similarly there's a question: How many app writers will read manual for
> older ppc64 architecture and write apps that won't work reliably on
> POWER10? Again, I have no idea.
>
> So the prctl would be IMHO a nice safety belt but I'm not 100% certain it
> will be needed...
>
>
-aneesh
^ permalink raw reply
* Re: [PATCH v1 3/4] KVM: PPC: Book3S HV: migrate remaining normal-GFNs to secure-GFNs in H_SVM_INIT_DONE
From: Bharata B Rao @ 2020-06-01 11:55 UTC (permalink / raw)
To: Ram Pai
Cc: ldufour, cclaudio, kvm-ppc, aneesh.kumar, sukadev, linuxppc-dev,
bauerman, david
In-Reply-To: <1590892071-25549-4-git-send-email-linuxram@us.ibm.com>
On Sat, May 30, 2020 at 07:27:50PM -0700, Ram Pai wrote:
> H_SVM_INIT_DONE incorrectly assumes that the Ultravisor has explicitly
> called H_SVM_PAGE_IN for all secure pages.
I don't think that is quite true. HV doesn't assume anything about
secure pages by itself.
> These GFNs continue to be
> normal GFNs associated with normal PFNs; when infact, these GFNs should
> have been secure GFNs associated with device PFNs.
Transition to secure state is driven by SVM/UV and HV just responds to
hcalls by issuing appropriate uvcalls. SVM/UV is in the best position to
determine the required pages that need to be moved into secure side.
HV just responds to it and tracks such pages as device private pages.
If SVM/UV doesn't get in all the pages to secure side by the time
of H_SVM_INIT_DONE, the remaining pages are just normal (shared or
otherwise) pages as far as HV is concerned. Why should HV assume that
SVM/UV didn't ask for a few pages and hence push those pages during
H_SVM_INIT_DONE?
I think UV should drive the movement of pages into secure side both
of boot-time SVM memory and hot-plugged memory. HV does memslot
registration uvcall when new memory is plugged in, UV should explicitly
get the required pages in at that time instead of expecting HV to drive
the same.
> +static int uv_migrate_mem_slot(struct kvm *kvm,
> + const struct kvm_memory_slot *memslot)
> +{
> + unsigned long gfn = memslot->base_gfn;
> + unsigned long end;
> + bool downgrade = false;
> + struct vm_area_struct *vma;
> + int i, ret = 0;
> + unsigned long start = gfn_to_hva(kvm, gfn);
> +
> + if (kvm_is_error_hva(start))
> + return H_STATE;
> +
> + end = start + (memslot->npages << PAGE_SHIFT);
> +
> + down_write(&kvm->mm->mmap_sem);
> +
> + mutex_lock(&kvm->arch.uvmem_lock);
> + vma = find_vma_intersection(kvm->mm, start, end);
> + if (!vma || vma->vm_start > start || vma->vm_end < end) {
> + ret = H_STATE;
> + goto out_unlock;
> + }
> +
> + ret = ksm_madvise(vma, vma->vm_start, vma->vm_end,
> + MADV_UNMERGEABLE, &vma->vm_flags);
> + downgrade_write(&kvm->mm->mmap_sem);
> + downgrade = true;
> + if (ret) {
> + ret = H_STATE;
> + goto out_unlock;
> + }
> +
> + for (i = 0; i < memslot->npages; i++, ++gfn) {
> + /* skip paged-in pages and shared pages */
> + if (kvmppc_gfn_is_uvmem_pfn(gfn, kvm, NULL) ||
> + kvmppc_gfn_is_uvmem_shared(gfn, kvm))
> + continue;
> +
> + start = gfn_to_hva(kvm, gfn);
> + end = start + (1UL << PAGE_SHIFT);
> + ret = kvmppc_svm_migrate_page(vma, start, end,
> + (gfn << PAGE_SHIFT), kvm, PAGE_SHIFT, false);
> +
> + if (ret)
> + goto out_unlock;
> + }
Is there a guarantee that the vma you got for the start address remains
valid for all the addresses till end in a memslot? If not, you should
re-get the vma for the current address in each iteration I suppose.
Regards,
Bharata.
^ permalink raw reply
* Re: [RFC PATCH 1/2] libnvdimm: Add prctl control for disabling synchronous fault support.
From: Jan Kara @ 2020-06-01 10:09 UTC (permalink / raw)
To: Aneesh Kumar K.V
Cc: Jan Kara, linux-nvdimm, jack, Jeff Moyer, oohall, dan.j.williams,
Michal Suchánek, linuxppc-dev
In-Reply-To: <7e8ee9e3-4d4d-e4b9-913b-1c2448adc62a@linux.ibm.com>
On Fri 29-05-20 16:25:35, Aneesh Kumar K.V wrote:
> On 5/29/20 3:22 PM, Jan Kara wrote:
> > On Fri 29-05-20 15:07:31, Aneesh Kumar K.V wrote:
> > > Thanks Michal. I also missed Jeff in this email thread.
> >
> > And I think you'll also need some of the sched maintainers for the prctl
> > bits...
> >
> > > On 5/29/20 3:03 PM, Michal Suchánek wrote:
> > > > Adding Jan
> > > >
> > > > On Fri, May 29, 2020 at 11:11:39AM +0530, Aneesh Kumar K.V wrote:
> > > > > With POWER10, architecture is adding new pmem flush and sync instructions.
> > > > > The kernel should prevent the usage of MAP_SYNC if applications are not using
> > > > > the new instructions on newer hardware.
> > > > >
> > > > > This patch adds a prctl option MAP_SYNC_ENABLE that can be used to enable
> > > > > the usage of MAP_SYNC. The kernel config option is added to allow the user
> > > > > to control whether MAP_SYNC should be enabled by default or not.
> > > > >
> > > > > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> > ...
> > > > > diff --git a/kernel/fork.c b/kernel/fork.c
> > > > > index 8c700f881d92..d5a9a363e81e 100644
> > > > > --- a/kernel/fork.c
> > > > > +++ b/kernel/fork.c
> > > > > @@ -963,6 +963,12 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock);
> > > > > static unsigned long default_dump_filter = MMF_DUMP_FILTER_DEFAULT;
> > > > > +#ifdef CONFIG_ARCH_MAP_SYNC_DISABLE
> > > > > +unsigned long default_map_sync_mask = MMF_DISABLE_MAP_SYNC_MASK;
> > > > > +#else
> > > > > +unsigned long default_map_sync_mask = 0;
> > > > > +#endif
> > > > > +
> >
> > I'm not sure CONFIG is really the right approach here. For a distro that would
> > basically mean to disable MAP_SYNC for all PPC kernels unless application
> > explicitly uses the right prctl. Shouldn't we rather initialize
> > default_map_sync_mask on boot based on whether the CPU we run on requires
> > new flush instructions or not? Otherwise the patch looks sensible.
> >
>
> yes that is correct. We ideally want to deny MAP_SYNC only w.r.t POWER10.
> But on a virtualized platform there is no easy way to detect that. We could
> ideally hook this into the nvdimm driver where we look at the new compat
> string ibm,persistent-memory-v2 and then disable MAP_SYNC
> if we find a device with the specific value.
Hum, couldn't we set some flag for nvdimm devices with
"ibm,persistent-memory-v2" property and then check it during mmap(2) time
and when the device has this propery and the mmap(2) caller doesn't have
the prctl set, we'd disallow MAP_SYNC? That should make things mostly
seamless, shouldn't it? Only apps that want to use MAP_SYNC on these
devices would need to use prctl(MMF_DISABLE_MAP_SYNC, 0) but then these
applications need to be aware of new instructions so this isn't that much
additional burden...
> With that I am wondering should we even have this patch? Can we expect
> userspace get updated to use new instruction?.
>
> With ppc64 we never had a real persistent memory device available for end
> user to try. The available persistent memory stack was using vPMEM which was
> presented as a volatile memory region for which there is no need to use any
> of the flush instructions. We could safely assume that as we get
> applications certified/verified for working with pmem device on ppc64, they
> would all be using the new instructions?
This is a bit of a gamble... I don't have too much trust in certification /
verification because only the "big players" may do powerfail testing
throughout enough that they'd uncover these problems. So the question
really is: How many apps are out there using MAP_SYNC on ppc64? Hopefully
not many given the HW didn't ship yet as you wrote but I have no real clue.
Similarly there's a question: How many app writers will read manual for
older ppc64 architecture and write apps that won't work reliably on
POWER10? Again, I have no idea.
So the prctl would be IMHO a nice safety belt but I'm not 100% certain it
will be needed...
Honza
--
Jan Kara <jack@suse.com>
SUSE Labs, CR
^ permalink raw reply
* Re: [RFC PATCH 1/2] libnvdimm: Add prctl control for disabling synchronous fault support.
From: Jan Kara @ 2020-06-01 9:50 UTC (permalink / raw)
To: Dan Williams
Cc: Jan Kara, linux-nvdimm, Aneesh Kumar K.V, jack, Jeff Moyer,
Oliver O'Halloran, Michal Suchánek, linuxppc-dev
In-Reply-To: <CAPcyv4i7k7t8is_6FKAWbWsGHVO0kvj-OqqqJTzw=VS7xtZVvQ@mail.gmail.com>
On Sat 30-05-20 09:35:19, Dan Williams wrote:
> On Sat, May 30, 2020 at 12:18 AM Aneesh Kumar K.V
> <aneesh.kumar@linux.ibm.com> wrote:
> >
> > On 5/30/20 12:52 AM, Dan Williams wrote:
> > > On Fri, May 29, 2020 at 3:55 AM Aneesh Kumar K.V
> > > <aneesh.kumar@linux.ibm.com> wrote:
> > >>
> > >> On 5/29/20 3:22 PM, Jan Kara wrote:
> > >>> Hi!
> > >>>
> > >>> On Fri 29-05-20 15:07:31, Aneesh Kumar K.V wrote:
> > >>>> Thanks Michal. I also missed Jeff in this email thread.
> > >>>
> > >>> And I think you'll also need some of the sched maintainers for the prctl
> > >>> bits...
> > >>>
> > >>>> On 5/29/20 3:03 PM, Michal Suchánek wrote:
> > >>>>> Adding Jan
> > >>>>>
> > >>>>> On Fri, May 29, 2020 at 11:11:39AM +0530, Aneesh Kumar K.V wrote:
> > >>>>>> With POWER10, architecture is adding new pmem flush and sync instructions.
> > >>>>>> The kernel should prevent the usage of MAP_SYNC if applications are not using
> > >>>>>> the new instructions on newer hardware.
> > >>>>>>
> > >>>>>> This patch adds a prctl option MAP_SYNC_ENABLE that can be used to enable
> > >>>>>> the usage of MAP_SYNC. The kernel config option is added to allow the user
> > >>>>>> to control whether MAP_SYNC should be enabled by default or not.
> > >>>>>>
> > >>>>>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> > >>> ...
> > >>>>>> diff --git a/kernel/fork.c b/kernel/fork.c
> > >>>>>> index 8c700f881d92..d5a9a363e81e 100644
> > >>>>>> --- a/kernel/fork.c
> > >>>>>> +++ b/kernel/fork.c
> > >>>>>> @@ -963,6 +963,12 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock);
> > >>>>>> static unsigned long default_dump_filter = MMF_DUMP_FILTER_DEFAULT;
> > >>>>>> +#ifdef CONFIG_ARCH_MAP_SYNC_DISABLE
> > >>>>>> +unsigned long default_map_sync_mask = MMF_DISABLE_MAP_SYNC_MASK;
> > >>>>>> +#else
> > >>>>>> +unsigned long default_map_sync_mask = 0;
> > >>>>>> +#endif
> > >>>>>> +
> > >>>
> > >>> I'm not sure CONFIG is really the right approach here. For a distro that would
> > >>> basically mean to disable MAP_SYNC for all PPC kernels unless application
> > >>> explicitly uses the right prctl. Shouldn't we rather initialize
> > >>> default_map_sync_mask on boot based on whether the CPU we run on requires
> > >>> new flush instructions or not? Otherwise the patch looks sensible.
> > >>>
> > >>
> > >> yes that is correct. We ideally want to deny MAP_SYNC only w.r.t
> > >> POWER10. But on a virtualized platform there is no easy way to detect
> > >> that. We could ideally hook this into the nvdimm driver where we look at
> > >> the new compat string ibm,persistent-memory-v2 and then disable MAP_SYNC
> > >> if we find a device with the specific value.
> > >>
> > >> BTW with the recent changes I posted for the nvdimm driver, older kernel
> > >> won't initialize persistent memory device on newer hardware. Newer
> > >> hardware will present the device to OS with a different device tree
> > >> compat string.
> > >>
> > >> My expectation w.r.t this patch was, Distro would want to mark
> > >> CONFIG_ARCH_MAP_SYNC_DISABLE=n based on the different application
> > >> certification. Otherwise application will have to end up calling the
> > >> prctl(MMF_DISABLE_MAP_SYNC, 0) any way. If that is the case, should this
> > >> be dependent on P10?
> > >>
> > >> With that I am wondering should we even have this patch? Can we expect
> > >> userspace get updated to use new instruction?.
> > >>
> > >> With ppc64 we never had a real persistent memory device available for
> > >> end user to try. The available persistent memory stack was using vPMEM
> > >> which was presented as a volatile memory region for which there is no
> > >> need to use any of the flush instructions. We could safely assume that
> > >> as we get applications certified/verified for working with pmem device
> > >> on ppc64, they would all be using the new instructions?
> > >
> > > I think prctl is the wrong interface for this. I was thinking a sysfs
> > > interface along the same lines as /sys/block/pmemX/dax/write_cache.
> > > That attribute is toggling DAXDEV_WRITE_CACHE for the determination of
> > > whether the platform or the kernel needs to handle cache flushing
> > > relative to power loss. A similar attribute can be established for
> > > DAXDEV_SYNC, it would simply default to off based on a configuration
> > > time policy, but be dynamically changeable at runtime via sysfs.
> > >
> > > These flags are device properties that affect the kernel and
> > > userspace's handling of persistence.
> > >
> >
> > That will not handle the scenario with multiple applications using the
> > same fsdax mount point where one is updated to use the new instruction
> > and the other is not.
>
> Right, it needs to be a global setting / flag day to switch from one
> regime to another. Per-process control is a recipe for disaster.
First I'd like to mention that hopefully the concern is mostly theoretical
since as Aneesh wrote above, real persistent memory never shipped for PPC
and so there are very few apps (if any) using the old way to ensure cache
flushing.
But I'd like to understand why do you think per-process control is a recipe
for disaster? Because from my POV the sysfs interface you propose is actually
difficult to use in practice. As a distributor, you have hard time picking
the default because you have a choice between picking safe option which is
going to confuse users because of failing MAP_SYNC and unsafe option where
everyone will be happy until someone looses data because of some ancient
application using wrong instructions to persist data. Poor experience for
users in either way. And when distro defaults to "safe option", then the
burden is on the sysadmin to toggle the switch but how is he supposed to
decide when that is safe? First he has to understand what the problem
actually is, then he has to audit all the applications using pmem whether
they use the new instruction - which is IMO a lot of effort if you have a
couple of applications and practically infeasible if you have more of them.
So IMO the burden should be *on the application* to declare that it is
aware of the new instructions to flush pmem on the platform and only to
such application the kernel should give the trust to use MAP_SYNC mappings.
Honza
--
Jan Kara <jack@suse.com>
SUSE Labs, CR
^ permalink raw reply
* Re: [PATCH 8/8] macintosh/adb-iop: Implement SRQ autopolling
From: Geert Uytterhoeven @ 2020-06-01 9:12 UTC (permalink / raw)
To: Finn Thain
Cc: linux-m68k, linuxppc-dev, Linux Kernel Mailing List,
Joshua Thompson
In-Reply-To: <alpine.LNX.2.22.394.2006011006080.8@nippy.intranet>
Hi Finn,
On Mon, Jun 1, 2020 at 2:15 AM Finn Thain <fthain@telegraphics.com.au> wrote:
> On Sun, 31 May 2020, Geert Uytterhoeven wrote:
> > On Sun, May 31, 2020 at 1:20 AM Finn Thain <fthain@telegraphics.com.au> wrote:
> > > arch/m68k/include/asm/adb_iop.h | 1 +
> > > drivers/macintosh/adb-iop.c | 32 ++++++++++++++++++++++++++------
> >
> > As this header file is used by a single source file only, perhaps it
> > should just be absorbed by the latter?
>
> Sure, it could be absorbed by both asm/mac_iop.h and
> drivers/macintosh/adb-iop.c but I don't see the point...
asm/mac_iop.h doesn't include asm/adb_iop.h (at least not in my tree,
but perhaps you have plans to change that?), so there's only a single
user.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply
* Re: [PATCH 8/8] macintosh/adb-iop: Implement SRQ autopolling
From: Geert Uytterhoeven @ 2020-06-01 9:10 UTC (permalink / raw)
To: Brad Boyer; +Cc: linux-m68k, linuxppc-dev, Joshua Thompson, Finn Thain
In-Reply-To: <20200531200140.GA27809@allandria.com>
Hi Brad,
On Sun, May 31, 2020 at 10:01 PM Brad Boyer <flar@allandria.com> wrote:
> On Sun, May 31, 2020 at 10:38:04AM +0200, Geert Uytterhoeven wrote:
> > > arch/m68k/include/asm/adb_iop.h | 1 +
> > As this header file is used by a single source file only, perhaps it should
> > just be absorbed by the latter?
> > Then you no longer need my Acked-by for future changes ;-)
>
> While I don't really feel involved in this specific change (although I
> was one of the testers when the driver was first written), I am a little
> curious about the current coding standards. This header is pretty much
> just a declaration of the hardware interface, of which there are many
> in this directory. Is it better to just define all the offsets and bits
> for hardware registers inside the driver? We used to always put them in
> headers like this, but is that not the current standard? Would it be
> cleaner to put such headers in the directory with the driver effectively
> making them private? I seem to see quite a bit of that as well.
The idea behind header files is to share definitions among multipe
source files, right? It seems there is only one user of this header
file, so no sharing is involved, and thus these definitions are
de-facto private to the driver. Hence, the hardware declarations
could be absorbed by the driver source file.
In this case having two separate files makes maintenance more
difficult, as the two files belong to different maintainer spaces
(drivers/macintosh/ and arch/m68k/).
In general, moving header files to the driver directory is an option,
if nothing outside the driver directory needs it.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply
* Re: [PATCH v5] powerpc/irq: inline call_do_irq() and call_do_softirq() on PPC32
From: Christophe Leroy @ 2020-06-01 7:26 UTC (permalink / raw)
To: Michael Ellerman; +Cc: Paul Mackerras, linuxppc-dev, linux-kernel
In-Reply-To: <72a6cd86137b2a7ab835213cf5c74df6ed2f6ea7.1575739197.git.christophe.leroy@c-s.fr>
Hi Michael,
Le 07/12/2019 à 18:20, Christophe Leroy a écrit :
> call_do_irq() and call_do_softirq() are simple enough to be
> worth inlining.
>
> Inlining them avoids an mflr/mtlr pair plus a save/reload on stack.
> It also allows GCC to keep the saved ksp_limit in an nonvolatile reg.
>
> This is inspired from S390 arch. Several other arches do more or
> less the same. The way sparc arch does seems odd thought.
>
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
> Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Anything more I need to do for this patch to get merged ?
Thanks
Christophe
>
> ---
> v2: no change.
> v3: no change.
> v4:
> - comment reminding the purpose of the inline asm block.
> - added r2 as clobbered reg
> v5:
> - Limiting the change to PPC32 for now.
> - removed r2 from the clobbered regs list (on PPC32 r2 points to current all the time)
> - Removed patch 1 and merged ksp_limit handling in here.
> ---
> arch/powerpc/include/asm/irq.h | 2 ++
> arch/powerpc/kernel/irq.c | 48 ++++++++++++++++++++++++++++++++++++++++++
> arch/powerpc/kernel/misc_32.S | 39 ----------------------------------
> 3 files changed, 50 insertions(+), 39 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/irq.h b/arch/powerpc/include/asm/irq.h
> index 814dfab7e392..e4a92f0b4ad4 100644
> --- a/arch/powerpc/include/asm/irq.h
> +++ b/arch/powerpc/include/asm/irq.h
> @@ -56,8 +56,10 @@ extern void *mcheckirq_ctx[NR_CPUS];
> extern void *hardirq_ctx[NR_CPUS];
> extern void *softirq_ctx[NR_CPUS];
>
> +#ifdef CONFIG_PPC64
> void call_do_softirq(void *sp);
> void call_do_irq(struct pt_regs *regs, void *sp);
> +#endif
> extern void do_IRQ(struct pt_regs *regs);
> extern void __init init_IRQ(void);
> extern void __do_irq(struct pt_regs *regs);
> diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
> index 5645bc9cbc09..240eca12c71d 100644
> --- a/arch/powerpc/kernel/irq.c
> +++ b/arch/powerpc/kernel/irq.c
> @@ -611,6 +611,54 @@ static inline void check_stack_overflow(void)
> #endif
> }
>
> +#ifdef CONFIG_PPC32
> +static inline void call_do_softirq(const void *sp)
> +{
> + register unsigned long ret asm("r3");
> + unsigned long limit = current->thread.ksp_limit;
> +
> + /* Adjust the stack limit */
> + current->thread.ksp_limit = (unsigned long)sp;
> +
> + /* Temporarily switch r1 to sp, call __do_softirq() then restore r1. */
> + asm volatile(
> + " "PPC_STLU" 1, %2(%1);\n"
> + " mr 1, %1;\n"
> + " bl %3;\n"
> + " "PPC_LL" 1, 0(1);\n" :
> + "=r"(ret) :
> + "b"(sp), "i"(THREAD_SIZE - STACK_FRAME_OVERHEAD), "i"(__do_softirq) :
> + "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6", "cr7",
> + "r0", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12");
> +
> + /* Restore stack limit */
> + current->thread.ksp_limit = limit;
> +}
> +
> +static inline void call_do_irq(struct pt_regs *regs, void *sp)
> +{
> + register unsigned long r3 asm("r3") = (unsigned long)regs;
> + unsigned long limit = current->thread.ksp_limit;
> +
> + /* Adjust the stack limit */
> + current->thread.ksp_limit = (unsigned long)sp;
> +
> + /* Temporarily switch r1 to sp, call __do_irq() then restore r1 */
> + asm volatile(
> + " "PPC_STLU" 1, %2(%1);\n"
> + " mr 1, %1;\n"
> + " bl %3;\n"
> + " "PPC_LL" 1, 0(1);\n" :
> + "+r"(r3) :
> + "b"(sp), "i"(THREAD_SIZE - STACK_FRAME_OVERHEAD), "i"(__do_irq) :
> + "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6", "cr7",
> + "r0", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12");
> +
> + /* Restore stack limit */
> + current->thread.ksp_limit = limit;
> +}
> +#endif
> +
> void __do_irq(struct pt_regs *regs)
> {
> unsigned int irq;
> diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
> index d80212be8698..341a3cd199cb 100644
> --- a/arch/powerpc/kernel/misc_32.S
> +++ b/arch/powerpc/kernel/misc_32.S
> @@ -28,45 +28,6 @@
> .text
>
> /*
> - * We store the saved ksp_limit in the unused part
> - * of the STACK_FRAME_OVERHEAD
> - */
> -_GLOBAL(call_do_softirq)
> - mflr r0
> - stw r0,4(r1)
> - lwz r10,THREAD+KSP_LIMIT(r2)
> - stw r3, THREAD+KSP_LIMIT(r2)
> - stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
> - mr r1,r3
> - stw r10,8(r1)
> - bl __do_softirq
> - lwz r10,8(r1)
> - lwz r1,0(r1)
> - lwz r0,4(r1)
> - stw r10,THREAD+KSP_LIMIT(r2)
> - mtlr r0
> - blr
> -
> -/*
> - * void call_do_irq(struct pt_regs *regs, void *sp);
> - */
> -_GLOBAL(call_do_irq)
> - mflr r0
> - stw r0,4(r1)
> - lwz r10,THREAD+KSP_LIMIT(r2)
> - stw r4, THREAD+KSP_LIMIT(r2)
> - stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4)
> - mr r1,r4
> - stw r10,8(r1)
> - bl __do_irq
> - lwz r10,8(r1)
> - lwz r1,0(r1)
> - lwz r0,4(r1)
> - stw r10,THREAD+KSP_LIMIT(r2)
> - mtlr r0
> - blr
> -
> -/*
> * This returns the high 64 bits of the product of two 64-bit numbers.
> */
> _GLOBAL(mulhdu)
>
^ permalink raw reply
* [powerpc:next-test] BUILD SUCCESS e376ca093587eafd840bb0f9df04090e2a54249c
From: kbuild test robot @ 2020-06-01 5:19 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev
tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next-test
branch HEAD: e376ca093587eafd840bb0f9df04090e2a54249c powerpc/module_64: Use special stub for _mcount() with -mprofile-kernel
Warning in current branch:
kernel/events/hw_breakpoint.c:216:12: warning: no previous prototype for 'arch_reserve_bp_slot' [-Wmissing-prototypes]
kernel/events/hw_breakpoint.c:221:13: warning: no previous prototype for 'arch_release_bp_slot' [-Wmissing-prototypes]
Warning ids grouped by kconfigs:
recent_errors
|-- arm64-allmodconfig
| |-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_release_bp_slot
| `-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_reserve_bp_slot
|-- arm64-allyesconfig
| |-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_release_bp_slot
| `-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_reserve_bp_slot
|-- arm64-defconfig
| |-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_release_bp_slot
| `-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_reserve_bp_slot
|-- i386-allnoconfig
| |-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_release_bp_slot
| `-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_reserve_bp_slot
|-- i386-randconfig-m021-20200529
| |-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_release_bp_slot
| `-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_reserve_bp_slot
|-- i386-tinyconfig
| |-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_release_bp_slot
| `-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_reserve_bp_slot
|-- sh-shmin_defconfig
| |-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_release_bp_slot
| `-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_reserve_bp_slot
|-- x86_64-defconfig
| |-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_release_bp_slot
| `-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_reserve_bp_slot
`-- x86_64-randconfig-m001-20200531
|-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_release_bp_slot
`-- kernel-events-hw_breakpoint.c:warning:no-previous-prototype-for-arch_reserve_bp_slot
elapsed time: 3868m
configs tested: 143
configs skipped: 11
The following configs have been built successfully.
More configs may be tested in the coming days.
arm defconfig
arm allyesconfig
arm allmodconfig
arm allnoconfig
arm64 allyesconfig
arm64 defconfig
arm64 allmodconfig
arm64 allnoconfig
arm pxa3xx_defconfig
arm palmz72_defconfig
sh shmin_defconfig
ia64 zx1_defconfig
riscv rv32_defconfig
xtensa iss_defconfig
powerpc pasemi_defconfig
sparc sparc64_defconfig
mips decstation_64_defconfig
mips ath79_defconfig
mips allnoconfig
mips qi_lb60_defconfig
sh migor_defconfig
sh magicpanelr2_defconfig
mips sb1250_swarm_defconfig
powerpc mpc885_ads_defconfig
arm aspeed_g5_defconfig
mips maltaup_defconfig
arc nps_defconfig
sh rsk7269_defconfig
mips allyesconfig
ia64 generic_defconfig
m68k q40_defconfig
sh se7724_defconfig
mips malta_qemu_32r6_defconfig
mips e55_defconfig
mips lemote2f_defconfig
arm ebsa110_defconfig
arm lart_defconfig
sh microdev_defconfig
arm badge4_defconfig
arm oxnas_v6_defconfig
x86_64 defconfig
powerpc adder875_defconfig
mips ar7_defconfig
arm keystone_defconfig
arm viper_defconfig
arm pleb_defconfig
sh espt_defconfig
arm omap1_defconfig
arm spear13xx_defconfig
sparc64 allyesconfig
microblaze nommu_defconfig
arm davinci_all_defconfig
c6x defconfig
i386 allnoconfig
arm qcom_defconfig
powerpc amigaone_defconfig
nios2 10m50_defconfig
arm s3c6400_defconfig
openrisc defconfig
powerpc defconfig
arc tb10x_defconfig
arm mvebu_v7_defconfig
powerpc mpc7448_hpc2_defconfig
xtensa defconfig
s390 zfcpdump_defconfig
s390 allyesconfig
arm cns3420vb_defconfig
arm spear3xx_defconfig
i386 allyesconfig
i386 defconfig
i386 debian-10.3
ia64 allmodconfig
ia64 defconfig
ia64 allnoconfig
ia64 allyesconfig
m68k allmodconfig
m68k allnoconfig
m68k sun3_defconfig
m68k defconfig
m68k allyesconfig
nios2 defconfig
nios2 allyesconfig
c6x allyesconfig
c6x allnoconfig
openrisc allyesconfig
nds32 defconfig
nds32 allnoconfig
csky allyesconfig
csky defconfig
alpha defconfig
alpha allyesconfig
xtensa allyesconfig
h8300 allyesconfig
h8300 allmodconfig
arc defconfig
arc allyesconfig
sh allmodconfig
sh allnoconfig
microblaze allnoconfig
mips allmodconfig
parisc allnoconfig
parisc defconfig
parisc allyesconfig
parisc allmodconfig
powerpc allyesconfig
powerpc rhel-kconfig
powerpc allmodconfig
powerpc allnoconfig
i386 randconfig-a004-20200529
i386 randconfig-a001-20200529
i386 randconfig-a002-20200529
i386 randconfig-a006-20200529
i386 randconfig-a003-20200529
i386 randconfig-a005-20200529
i386 randconfig-a013-20200529
i386 randconfig-a011-20200529
i386 randconfig-a012-20200529
i386 randconfig-a015-20200529
i386 randconfig-a016-20200529
i386 randconfig-a014-20200529
riscv allyesconfig
riscv allnoconfig
riscv defconfig
riscv allmodconfig
s390 allnoconfig
s390 allmodconfig
s390 defconfig
sparc allyesconfig
sparc defconfig
sparc64 defconfig
sparc64 allnoconfig
sparc64 allmodconfig
um allmodconfig
um allnoconfig
um defconfig
um allyesconfig
x86_64 rhel
x86_64 rhel-7.6
x86_64 rhel-7.6-kselftests
x86_64 rhel-7.2-clear
x86_64 lkp
x86_64 fedora-25
x86_64 kexec
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
^ permalink raw reply
* [powerpc:fixes-test] BUILD SUCCESS 2f26ed1764b42a8c40d9c48441c73a70d805decf
From: kbuild test robot @ 2020-06-01 5:14 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev
tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git fixes-test
branch HEAD: 2f26ed1764b42a8c40d9c48441c73a70d805decf powerpc/64s: Disable sanitisers for C syscall/interrupt entry/exit code
elapsed time: 3867m
configs tested: 186
configs skipped: 14
The following configs have been built successfully.
More configs may be tested in the coming days.
arm defconfig
arm allyesconfig
arm allmodconfig
arm allnoconfig
arm64 allyesconfig
arm64 defconfig
arm64 allmodconfig
arm64 allnoconfig
arm pxa3xx_defconfig
arm palmz72_defconfig
sh shmin_defconfig
ia64 zx1_defconfig
riscv rv32_defconfig
um x86_64_defconfig
m68k m5249evb_defconfig
sh sh7770_generic_defconfig
arm vf610m4_defconfig
arm trizeps4_defconfig
powerpc pasemi_defconfig
sparc sparc64_defconfig
mips decstation_64_defconfig
mips ath79_defconfig
mips allnoconfig
mips qi_lb60_defconfig
sh migor_defconfig
sh magicpanelr2_defconfig
mips sb1250_swarm_defconfig
sh sh7763rdp_defconfig
s390 allnoconfig
mips tb0226_defconfig
m68k multi_defconfig
h8300 allyesconfig
sh sh03_defconfig
sh se7343_defconfig
arm badge4_defconfig
sh se7780_defconfig
powerpc mpc885_ads_defconfig
arm aspeed_g5_defconfig
mips maltaup_defconfig
arc nps_defconfig
sh rsk7269_defconfig
mips allyesconfig
ia64 generic_defconfig
arm mainstone_defconfig
arm hisi_defconfig
powerpc mpc83xx_defconfig
m68k allyesconfig
xtensa allyesconfig
sh sdk7780_defconfig
mips jmr3927_defconfig
riscv defconfig
sh cayman_defconfig
arm ebsa110_defconfig
arm lart_defconfig
sh microdev_defconfig
arm oxnas_v6_defconfig
x86_64 defconfig
powerpc adder875_defconfig
mips ar7_defconfig
arm keystone_defconfig
arm viper_defconfig
ia64 allnoconfig
powerpc pseries_defconfig
arm dove_defconfig
h8300 alldefconfig
arm pleb_defconfig
sh espt_defconfig
arm omap1_defconfig
arm spear13xx_defconfig
sparc64 allyesconfig
microblaze nommu_defconfig
arc axs101_defconfig
powerpc maple_defconfig
nds32 allnoconfig
sh allmodconfig
arm davinci_all_defconfig
c6x defconfig
i386 allnoconfig
powerpc defconfig
arc tb10x_defconfig
arm mvebu_v7_defconfig
powerpc mpc7448_hpc2_defconfig
xtensa defconfig
c6x dsk6455_defconfig
riscv nommu_virt_defconfig
sh apsh4ad0a_defconfig
openrisc defconfig
mips rb532_defconfig
arm assabet_defconfig
arc alldefconfig
xtensa common_defconfig
s390 zfcpdump_defconfig
s390 allyesconfig
arm cns3420vb_defconfig
arm spear3xx_defconfig
i386 allyesconfig
i386 defconfig
i386 debian-10.3
ia64 allmodconfig
ia64 defconfig
ia64 allyesconfig
m68k allmodconfig
m68k allnoconfig
m68k sun3_defconfig
m68k defconfig
nios2 defconfig
nios2 allyesconfig
c6x allyesconfig
c6x allnoconfig
openrisc allyesconfig
nds32 defconfig
csky allyesconfig
csky defconfig
alpha defconfig
alpha allyesconfig
h8300 allmodconfig
arc defconfig
arc allyesconfig
sh allnoconfig
microblaze allnoconfig
mips allmodconfig
parisc allnoconfig
parisc defconfig
parisc allyesconfig
parisc allmodconfig
powerpc allyesconfig
powerpc rhel-kconfig
powerpc allmodconfig
powerpc allnoconfig
i386 randconfig-a004-20200529
i386 randconfig-a001-20200529
i386 randconfig-a002-20200529
i386 randconfig-a006-20200529
i386 randconfig-a003-20200529
i386 randconfig-a005-20200529
i386 randconfig-a004-20200531
i386 randconfig-a003-20200531
i386 randconfig-a006-20200531
i386 randconfig-a002-20200531
i386 randconfig-a005-20200531
i386 randconfig-a001-20200531
x86_64 randconfig-a002-20200529
x86_64 randconfig-a006-20200529
x86_64 randconfig-a005-20200529
x86_64 randconfig-a001-20200529
x86_64 randconfig-a004-20200529
x86_64 randconfig-a003-20200529
x86_64 randconfig-a011-20200531
x86_64 randconfig-a016-20200531
x86_64 randconfig-a012-20200531
x86_64 randconfig-a014-20200531
x86_64 randconfig-a013-20200531
x86_64 randconfig-a015-20200531
i386 randconfig-a013-20200529
i386 randconfig-a011-20200529
i386 randconfig-a012-20200529
i386 randconfig-a015-20200529
i386 randconfig-a016-20200529
i386 randconfig-a014-20200529
i386 randconfig-a013-20200531
i386 randconfig-a012-20200531
i386 randconfig-a015-20200531
i386 randconfig-a011-20200531
i386 randconfig-a016-20200531
i386 randconfig-a014-20200531
riscv allyesconfig
riscv allnoconfig
riscv allmodconfig
s390 allmodconfig
s390 defconfig
sparc allyesconfig
sparc defconfig
sparc64 defconfig
sparc64 allnoconfig
sparc64 allmodconfig
um allmodconfig
um allnoconfig
um allyesconfig
um defconfig
x86_64 rhel
x86_64 rhel-7.6
x86_64 rhel-7.6-kselftests
x86_64 rhel-7.2-clear
x86_64 lkp
x86_64 fedora-25
x86_64 kexec
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
^ permalink raw reply
* [powerpc:merge] BUILD SUCCESS 00ec79b0b767994422c43792d73ff1327714a73f
From: kbuild test robot @ 2020-06-01 5:14 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev
tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git merge
branch HEAD: 00ec79b0b767994422c43792d73ff1327714a73f Automatic merge of 'master', 'next' and 'fixes' (2020-05-29 22:32)
elapsed time: 3865m
configs tested: 134
configs skipped: 6
The following configs have been built successfully.
More configs may be tested in the coming days.
arm defconfig
arm allyesconfig
arm allmodconfig
arm allnoconfig
arm64 allyesconfig
arm64 defconfig
arm64 allmodconfig
arm64 allnoconfig
powerpc pasemi_defconfig
sparc sparc64_defconfig
mips decstation_64_defconfig
mips ath79_defconfig
powerpc mpc885_ads_defconfig
arm aspeed_g5_defconfig
mips maltaup_defconfig
arc nps_defconfig
sh rsk7269_defconfig
ia64 generic_defconfig
xtensa allyesconfig
sh sdk7780_defconfig
mips jmr3927_defconfig
riscv defconfig
sh cayman_defconfig
arm ebsa110_defconfig
arm lart_defconfig
sh microdev_defconfig
x86_64 defconfig
arm badge4_defconfig
arm oxnas_v6_defconfig
arm pleb_defconfig
sh espt_defconfig
arm omap1_defconfig
arm spear13xx_defconfig
sparc64 allyesconfig
microblaze nommu_defconfig
arm davinci_all_defconfig
c6x defconfig
i386 allnoconfig
riscv rv32_defconfig
powerpc defconfig
arc tb10x_defconfig
arm mvebu_v7_defconfig
powerpc mpc7448_hpc2_defconfig
xtensa defconfig
s390 zfcpdump_defconfig
s390 allyesconfig
arm cns3420vb_defconfig
arm spear3xx_defconfig
sh landisk_defconfig
mips fuloong2e_defconfig
s390 allnoconfig
xtensa alldefconfig
arm lpd270_defconfig
i386 allyesconfig
i386 defconfig
i386 debian-10.3
ia64 allmodconfig
ia64 defconfig
ia64 allnoconfig
ia64 allyesconfig
m68k allmodconfig
m68k allnoconfig
m68k sun3_defconfig
m68k defconfig
m68k allyesconfig
nios2 defconfig
nios2 allyesconfig
openrisc defconfig
c6x allyesconfig
c6x allnoconfig
openrisc allyesconfig
csky defconfig
alpha defconfig
alpha allyesconfig
nds32 defconfig
nds32 allnoconfig
csky allyesconfig
h8300 allyesconfig
h8300 allmodconfig
arc defconfig
arc allyesconfig
sh allmodconfig
sh allnoconfig
microblaze allnoconfig
mips allyesconfig
mips allnoconfig
mips allmodconfig
parisc allnoconfig
parisc defconfig
parisc allyesconfig
parisc allmodconfig
powerpc allyesconfig
powerpc rhel-kconfig
powerpc allmodconfig
powerpc allnoconfig
i386 randconfig-a004-20200529
i386 randconfig-a001-20200529
i386 randconfig-a002-20200529
i386 randconfig-a006-20200529
i386 randconfig-a003-20200529
i386 randconfig-a005-20200529
i386 randconfig-a013-20200529
i386 randconfig-a011-20200529
i386 randconfig-a012-20200529
i386 randconfig-a015-20200529
i386 randconfig-a016-20200529
i386 randconfig-a014-20200529
x86_64 randconfig-a002-20200529
x86_64 randconfig-a006-20200529
x86_64 randconfig-a005-20200529
x86_64 randconfig-a001-20200529
x86_64 randconfig-a004-20200529
x86_64 randconfig-a003-20200529
riscv allyesconfig
riscv allnoconfig
riscv allmodconfig
s390 allmodconfig
s390 defconfig
sparc allyesconfig
sparc defconfig
sparc64 defconfig
sparc64 allnoconfig
sparc64 allmodconfig
um allnoconfig
um allyesconfig
um defconfig
um allmodconfig
x86_64 rhel
x86_64 rhel-7.6
x86_64 rhel-7.6-kselftests
x86_64 rhel-7.2-clear
x86_64 lkp
x86_64 fedora-25
x86_64 kexec
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
^ permalink raw reply
* Re: [PATCH v1 4/4] KVM: PPC: Book3S HV: migrate hot plugged memory
From: kbuild test robot @ 2020-06-01 4:45 UTC (permalink / raw)
To: Ram Pai, kvm-ppc, linuxppc-dev
Cc: ldufour, kbuild-all, bharata, aneesh.kumar, sukadev, bauerman
In-Reply-To: <1590892071-25549-5-git-send-email-linuxram@us.ibm.com>
[-- Attachment #1: Type: text/plain, Size: 2155 bytes --]
Hi Ram,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on powerpc/next]
[also build test ERROR on v5.7]
[cannot apply to next-20200529]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Ram-Pai/Migrate-non-migrated-pages-of-a-SVM/20200601-034649
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-defconfig (attached as .config)
compiler: powerpc64-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc
If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>
All errors (new ones prefixed by >>, old ones prefixed by <<):
arch/powerpc/kvm/book3s_64_mmu_radix.c:345:6: error: no previous prototype for 'kvmppc_radix_set_pte_at' [-Werror=missing-prototypes]
345 | void kvmppc_radix_set_pte_at(struct kvm *kvm, unsigned long addr,
| ^~~~~~~~~~~~~~~~~~~~~~~
In file included from arch/powerpc/kvm/book3s_64_mmu_radix.c:23:
>> arch/powerpc/include/asm/kvm_book3s_uvmem.h:89:12: error: 'uv_migrate_mem_slot' declared 'static' but never defined [-Werror=unused-function]
89 | static int uv_migrate_mem_slot(struct kvm *kvm,
| ^~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
vim +89 arch/powerpc/include/asm/kvm_book3s_uvmem.h
83
84 static inline void
85 kvmppc_uvmem_drop_pages(const struct kvm_memory_slot *free,
86 struct kvm *kvm, bool skip_page_out,
87 bool purge_gfn) { }
88
> 89 static int uv_migrate_mem_slot(struct kvm *kvm,
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 26147 bytes --]
^ permalink raw reply
* Re: [PATCH v1 4/4] KVM: PPC: Book3S HV: migrate hot plugged memory
From: kbuild test robot @ 2020-06-01 4:35 UTC (permalink / raw)
To: Ram Pai, kvm-ppc, linuxppc-dev
Cc: ldufour, kbuild-all, bharata, aneesh.kumar, sukadev, bauerman
In-Reply-To: <1590892071-25549-5-git-send-email-linuxram@us.ibm.com>
[-- Attachment #1: Type: text/plain, Size: 2082 bytes --]
Hi Ram,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on powerpc/next]
[also build test WARNING on v5.7]
[cannot apply to next-20200529]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Ram-Pai/Migrate-non-migrated-pages-of-a-SVM/20200601-034649
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-rhel-kconfig (attached as .config)
compiler: powerpc64le-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc
If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>
All warnings (new ones prefixed by >>, old ones prefixed by <<):
arch/powerpc/kvm/book3s_hv.c:3516:5: warning: no previous prototype for 'kvmhv_p9_guest_entry' [-Wmissing-prototypes]
3516 | int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
| ^~~~~~~~~~~~~~~~~~~~
In file included from arch/powerpc/kvm/book3s_hv.c:75:
>> arch/powerpc/include/asm/kvm_book3s_uvmem.h:89:12: warning: 'uv_migrate_mem_slot' used but never defined
89 | static int uv_migrate_mem_slot(struct kvm *kvm,
| ^~~~~~~~~~~~~~~~~~~
vim +/uv_migrate_mem_slot +89 arch/powerpc/include/asm/kvm_book3s_uvmem.h
83
84 static inline void
85 kvmppc_uvmem_drop_pages(const struct kvm_memory_slot *free,
86 struct kvm *kvm, bool skip_page_out,
87 bool purge_gfn) { }
88
> 89 static int uv_migrate_mem_slot(struct kvm *kvm,
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 15580 bytes --]
^ permalink raw reply
* Re: [PATCH v1 2/4] KVM: PPC: Book3S HV: track shared GFNs of secure VMs
From: kbuild test robot @ 2020-06-01 4:12 UTC (permalink / raw)
To: Ram Pai, kvm-ppc, linuxppc-dev
Cc: ldufour, kbuild-all, bharata, aneesh.kumar, sukadev, bauerman
In-Reply-To: <1590892071-25549-3-git-send-email-linuxram@us.ibm.com>
[-- Attachment #1: Type: text/plain, Size: 8401 bytes --]
Hi Ram,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on powerpc/next]
[also build test WARNING on v5.7 next-20200529]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Ram-Pai/Migrate-non-migrated-pages-of-a-SVM/20200601-034649
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-allyesconfig (attached as .config)
compiler: powerpc64-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc
If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>
All warnings (new ones prefixed by >>, old ones prefixed by <<):
arch/powerpc/kvm/book3s_hv_uvmem.c:158:6: warning: no previous prototype for 'kvmppc_uvmem_available' [-Wmissing-prototypes]
158 | bool kvmppc_uvmem_available(void)
| ^~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kvm/book3s_hv_uvmem.c:167:5: warning: no previous prototype for 'kvmppc_uvmem_slot_init' [-Wmissing-prototypes]
167 | int kvmppc_uvmem_slot_init(struct kvm *kvm, const struct kvm_memory_slot *slot)
| ^~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kvm/book3s_hv_uvmem.c:192:6: warning: no previous prototype for 'kvmppc_uvmem_slot_free' [-Wmissing-prototypes]
192 | void kvmppc_uvmem_slot_free(struct kvm *kvm, const struct kvm_memory_slot *slot)
| ^~~~~~~~~~~~~~~~~~~~~~
>> arch/powerpc/kvm/book3s_hv_uvmem.c:279:6: warning: no previous prototype for 'kvmppc_gfn_is_uvmem_shared' [-Wmissing-prototypes]
279 | bool kvmppc_gfn_is_uvmem_shared(unsigned long gfn, struct kvm *kvm)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kvm/book3s_hv_uvmem.c:293:15: warning: no previous prototype for 'kvmppc_h_svm_init_start' [-Wmissing-prototypes]
293 | unsigned long kvmppc_h_svm_init_start(struct kvm *kvm)
| ^~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kvm/book3s_hv_uvmem.c:335:15: warning: no previous prototype for 'kvmppc_h_svm_init_done' [-Wmissing-prototypes]
335 | unsigned long kvmppc_h_svm_init_done(struct kvm *kvm)
| ^~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kvm/book3s_hv_uvmem.c:356:6: warning: no previous prototype for 'kvmppc_uvmem_drop_pages' [-Wmissing-prototypes]
356 | void kvmppc_uvmem_drop_pages(const struct kvm_memory_slot *free,
| ^~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kvm/book3s_hv_uvmem.c:397:15: warning: no previous prototype for 'kvmppc_h_svm_init_abort' [-Wmissing-prototypes]
397 | unsigned long kvmppc_h_svm_init_abort(struct kvm *kvm)
| ^~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kvm/book3s_hv_uvmem.c:599:15: warning: no previous prototype for 'kvmppc_h_svm_page_in' [-Wmissing-prototypes]
599 | unsigned long kvmppc_h_svm_page_in(struct kvm *kvm, unsigned long gpa,
| ^~~~~~~~~~~~~~~~~~~~
arch/powerpc/kvm/book3s_hv_uvmem.c:784:1: warning: no previous prototype for 'kvmppc_h_svm_page_out' [-Wmissing-prototypes]
784 | kvmppc_h_svm_page_out(struct kvm *kvm, unsigned long gpa,
| ^~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kvm/book3s_hv_uvmem.c:822:5: warning: no previous prototype for 'kvmppc_send_page_to_uv' [-Wmissing-prototypes]
822 | int kvmppc_send_page_to_uv(struct kvm *kvm, unsigned long gfn)
| ^~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kvm/book3s_hv_uvmem.c:867:5: warning: no previous prototype for 'kvmppc_uvmem_init' [-Wmissing-prototypes]
867 | int kvmppc_uvmem_init(void)
| ^~~~~~~~~~~~~~~~~
arch/powerpc/kvm/book3s_hv_uvmem.c:922:6: warning: no previous prototype for 'kvmppc_uvmem_free' [-Wmissing-prototypes]
922 | void kvmppc_uvmem_free(void)
| ^~~~~~~~~~~~~~~~~
vim +/kvmppc_gfn_is_uvmem_shared +279 arch/powerpc/kvm/book3s_hv_uvmem.c
157
> 158 bool kvmppc_uvmem_available(void)
159 {
160 /*
161 * If kvmppc_uvmem_bitmap != NULL, then there is an ultravisor
162 * and our data structures have been initialized successfully.
163 */
164 return !!kvmppc_uvmem_bitmap;
165 }
166
167 int kvmppc_uvmem_slot_init(struct kvm *kvm, const struct kvm_memory_slot *slot)
168 {
169 struct kvmppc_uvmem_slot *p;
170
171 p = kzalloc(sizeof(*p), GFP_KERNEL);
172 if (!p)
173 return -ENOMEM;
174 p->pfns = vzalloc(array_size(slot->npages, sizeof(*p->pfns)));
175 if (!p->pfns) {
176 kfree(p);
177 return -ENOMEM;
178 }
179 p->nr_pfns = slot->npages;
180 p->base_pfn = slot->base_gfn;
181
182 mutex_lock(&kvm->arch.uvmem_lock);
183 list_add(&p->list, &kvm->arch.uvmem_pfns);
184 mutex_unlock(&kvm->arch.uvmem_lock);
185
186 return 0;
187 }
188
189 /*
190 * All device PFNs are already released by the time we come here.
191 */
192 void kvmppc_uvmem_slot_free(struct kvm *kvm, const struct kvm_memory_slot *slot)
193 {
194 struct kvmppc_uvmem_slot *p, *next;
195
196 mutex_lock(&kvm->arch.uvmem_lock);
197 list_for_each_entry_safe(p, next, &kvm->arch.uvmem_pfns, list) {
198 if (p->base_pfn == slot->base_gfn) {
199 vfree(p->pfns);
200 list_del(&p->list);
201 kfree(p);
202 break;
203 }
204 }
205 mutex_unlock(&kvm->arch.uvmem_lock);
206 }
207
208 static void kvmppc_uvmem_pfn_insert(unsigned long gfn, unsigned long uvmem_pfn,
209 struct kvm *kvm)
210 {
211 struct kvmppc_uvmem_slot *p;
212
213 list_for_each_entry(p, &kvm->arch.uvmem_pfns, list) {
214 if (gfn >= p->base_pfn && gfn < p->base_pfn + p->nr_pfns) {
215 unsigned long index = gfn - p->base_pfn;
216
217 p->pfns[index] = uvmem_pfn | KVMPPC_UVMEM_PFN;
218 return;
219 }
220 }
221 }
222
223 static void kvmppc_uvmem_pfn_remove(unsigned long gfn, struct kvm *kvm)
224 {
225 struct kvmppc_uvmem_slot *p;
226
227 list_for_each_entry(p, &kvm->arch.uvmem_pfns, list) {
228 if (gfn >= p->base_pfn && gfn < p->base_pfn + p->nr_pfns) {
229 /*
230 * Reset everything, but keep the KVMPPC_UVMEM_SHARED
231 * flag intact. A gfn continues to be shared or
232 * unshared, with or without an associated device pfn.
233 */
234 p->pfns[gfn - p->base_pfn] &= KVMPPC_UVMEM_SHARED;
235 return;
236 }
237 }
238 }
239
240 static bool kvmppc_gfn_is_uvmem_pfn(unsigned long gfn, struct kvm *kvm,
241 unsigned long *uvmem_pfn)
242 {
243 struct kvmppc_uvmem_slot *p;
244
245 list_for_each_entry(p, &kvm->arch.uvmem_pfns, list) {
246 if (gfn >= p->base_pfn && gfn < p->base_pfn + p->nr_pfns) {
247 unsigned long index = gfn - p->base_pfn;
248
249 if (p->pfns[index] & KVMPPC_UVMEM_PFN) {
250 if (uvmem_pfn)
251 *uvmem_pfn = p->pfns[index] &
252 KVMPPC_UVMEM_PFN_MASK;
253 return true;
254 } else
255 return false;
256 }
257 }
258 return false;
259 }
260
261 static void kvmppc_gfn_uvmem_shared(unsigned long gfn, struct kvm *kvm,
262 bool set)
263 {
264 struct kvmppc_uvmem_slot *p;
265
266 list_for_each_entry(p, &kvm->arch.uvmem_pfns, list) {
267 if (gfn >= p->base_pfn && gfn < p->base_pfn + p->nr_pfns) {
268 unsigned long index = gfn - p->base_pfn;
269
270 if (set)
271 p->pfns[index] |= KVMPPC_UVMEM_SHARED;
272 else
273 p->pfns[index] &= ~KVMPPC_UVMEM_SHARED;
274 return;
275 }
276 }
277 }
278
> 279 bool kvmppc_gfn_is_uvmem_shared(unsigned long gfn, struct kvm *kvm)
280 {
281 struct kvmppc_uvmem_slot *p;
282
283 list_for_each_entry(p, &kvm->arch.uvmem_pfns, list) {
284 if (gfn >= p->base_pfn && gfn < p->base_pfn + p->nr_pfns) {
285 unsigned long index = gfn - p->base_pfn;
286
287 return (p->pfns[index] & KVMPPC_UVMEM_SHARED);
288 }
289 }
290 return false;
291 }
292
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 66040 bytes --]
^ permalink raw reply
* Re: [RFC][PATCH 0/2] Add support for using reserved memory for ima buffer pass
From: Prakhar Srivastava @ 2020-06-01 4:05 UTC (permalink / raw)
To: Thiago Jung Bauermann
Cc: Mark Rutland, kstewart, gregkh, bhsharma, tao.li, zohar, paulus,
vincenzo.frascino, will, Rob Herring, nramas, frowand.list,
masahiroy, jmorris, takahiro.akashi, linux-arm-kernel,
catalin.marinas, serge, devicetree, pasha.tatashin, hsinyi,
tusharsu, tglx, allison, christophe.leroy, mbrugger, balajib,
dmitry.kasatkin, linux-kernel, linux-security-module, james.morse,
linux-integrity, linuxppc-dev
In-Reply-To: <87v9knpa36.fsf@morokweng.localdomain>
On 5/22/20 9:08 PM, Thiago Jung Bauermann wrote:
>
> Hello Prakhar,
>
> Prakhar Srivastava <prsriva@linux.microsoft.com> writes:
>
>> On 5/12/20 4:05 PM, Rob Herring wrote:
>>> On Wed, May 06, 2020 at 10:50:04PM -0700, Prakhar Srivastava wrote:
>>>> Hi Mark,
>>>
>>> Please don't top post.
>>>
>>>> This patch set currently only address the Pure DT implementation.
>>>> EFI and ACPI implementations will be posted in subsequent patchsets.
>>>>
>>>> The logs are intended to be carried over the kexec and once read the
>>>> logs are no longer needed and in prior conversation with James(
>>>> https://lore.kernel.org/linux-arm-kernel/0053eb68-0905-4679-c97a-00c5cb6f1abb@arm.com/)
>>>> the apporach of using a chosen node doesn't
>>>> support the case.
>>>>
>>>> The DT entries make the reservation permanent and thus doesnt need kernel
>>>> segments to be used for this, however using a chosen-node with
>>>> reserved memory only changes the node information but memory still is
>>>> reserved via reserved-memory section.
>>>
>>> I think Mark's point was whether it needs to be permanent. We don't
>>> hardcode the initrd address for example.
>>>
>> Thankyou for clarifying my misunderstanding, i am modelling this keeping to the
>> TPM log implementation that uses a reserved memory. I will rev up the version
>> with chosen-node support.
>> That will make the memory reservation free after use.
>
> Nice. Do you intend to use the same property that powerpc uses
> (linux,ima-kexec-buffer)?
>
I was naming it ima-buffer, but naming is not a huge concern.
I will use linux,ima-kexec-buffer.
>>>> On 5/5/20 2:59 AM, Mark Rutland wrote:
>>>>> Hi Prakhar,
>>>>>
>>>>> On Mon, May 04, 2020 at 01:38:27PM -0700, Prakhar Srivastava wrote:
>>>>>> IMA during kexec(kexec file load) verifies the kernel signature and measures
>>>
>>> What's IMAIMA is a LSM attempting to detect if files have been accidentally or
>> maliciously altered, both remotely and locally, it can also be used
>> to appraise a file's measurement against a "good" value stored as an extended
>> attribute, and enforce local file integrity.
>>
>> IMA also validates and measures the signers of the kernel and initrd
>> during kexec. The measurements are extended to PCR 10(configurable) and the logs
>> stored in memory, however once kexec'd the logs are lost. Kexec is used as
>> secondary boot loader in may use cases and loosing the signer
>> creates a security hole.
>>
>> This patch is an implementation to carry over the logs and making it
>> possible to remotely validate the signers of the kernel and initrd. Such a
>> support exits only in powerpc.
>> This patch makes the carry over of logs architecture independent and puts the
>> complexity in a driver.
>
> If I'm not mistaken, the code at arch/powerpc/kexec/ima.c isn't actually
> powerpc-specific. It could be moved to an arch-independent directory and
> used by any other architecture which supports device trees.
>
> I think that's the simplest way forward. And to be honest I'm still
> trying to understand why you didn't take that approach. Did you try it
> and hit some obstacle or noticed a disadvantage for your use case?
>
The approach i have in this patch set is to provide an abstraction layer
that can be called from any architecture.
However taking a deeper look only the setup dtb is probably architecture
specific, only because the architecture specific kexec sets up the
device tree. I can also move the code up in security/ima. However i do
have some concerns with layering. I am hoping you can provide me with
some guidance in this aspect, i will send you the patch i am working on
to get some early feedback.
Thanks,
Prakhar Srivastava
> --
> Thiago Jung Bauermann
> IBM Linux Technology Center
>
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