KUEP implements the update of user segment registers.
Move it into mmu-hash.h in order to use it from other places.
And inline kuep_lock() and kuep_unlock() and remove kuep.c
Signed-off-by: Christophe Leroy
---
arch/powerpc/include/asm/book3s/32/mmu-hash.h | 27 +
arch/powerpc/incl
switch_mmu_context() does things that can easily be done in C.
For updating user segments, we have update_user_segments().
As mentionned in commit b5efec00b671 ("powerpc/32s: Move KUEP
locking/unlocking in C"), update_user_segments() has the loop
unrolled which is a significant performance gain.
Michal Suchánek writes:
> On Mon, May 03, 2021 at 01:37:57PM +0200, Andreas Schwab wrote:
>> Should this add a tag to the module vermagic?
>
> Would the modues link even if the vermagic was not changed?
Most modules will require some symbols from the kernel, and those will
be dot symbols, which w
Commit b1c5356e873c ("KVM: PPC: Convert to the gfn-based MMU notifier
callbacks") causes unmap_gfn_range and age_gfn callbacks to only work
on the first gfn in the range. It also makes the aging callbacks call
into both radix and hash aging functions for radix guests. Fix this.
Add warnings for th
On Tue, May 04, 2021 at 10:15:34PM +1000, Michael Ellerman wrote:
> Segher Boessenkool writes:
> > On Mon, May 03, 2021 at 10:51:41AM +1000, Nicholas Piggin wrote:
> >> then ELF ABIv2 is more explanatory about it being an abi change
> >> rather than base elf change, even if it's not the "correct"
On 04 May 2021 at 05:17pm, Christophe Leroy wrote:
Le 04/05/2021 à 16:59, Christian Zigotzky a écrit :
On 04 May 2021 at 04:41pm Christophe Leroy wrote:
Le 04/05/2021 à 13:02, Christian Zigotzky a écrit :
On 04 May 2021 at 12:07pm, Christian Zigotzky wrote:
On 04 May 2021 at 11:49am, Christop
On Wed, May 05, 2021 at 10:07:29PM +1000, Michael Ellerman wrote:
> Michal Suchánek writes:
> > On Mon, May 03, 2021 at 01:37:57PM +0200, Andreas Schwab wrote:
> >> Should this add a tag to the module vermagic?
> >
> > Would the modues link even if the vermagic was not changed?
>
> Most modules w
Following PACA related items are not used anymore by ASM code:
PACA_SIZE, PACACONTEXTID, PACALOWSLICESPSIZE, PACAHIGHSLICEPSIZE,
PACA_SLB_ADDR_LIMIT, MMUPSIZEDEFSIZE, PACASLBCACHE, PACASLBCACHEPTR,
PACASTABRR, PACAVMALLOCSLLP, MMUPSIZESLLP, PACACONTEXTSLLP,
PACALPPACAPTR, LPPACA_DTLIDX and PACA_DTL
mm_ctx_id and mm_ctx_slb_addr_limit are not used anymore.
Remove them.
Reviewed-by: Nicholas Piggin
Signed-off-by: Christophe Leroy
---
arch/powerpc/include/asm/paca.h | 2 --
arch/powerpc/kernel/paca.c | 2 --
2 files changed, 4 deletions(-)
diff --git a/arch/powerpc/include/asm/paca.h
Le 05/05/2021 à 00:30, Nathan Lynch a écrit :
Hi Laurent,
Hi Nathan,
Thanks for your review.
Bear with me while I work through the commit message:
Laurent Dufour writes:
After a LPM, the device tree node ibm,dynamic-reconfiguration-memory may be
updated by the hypervisor in the case the N
Hello,
looks like the ABI flags are not correctly applied when cross-compiling.
While building natively success of BTFIDS depends on the kernel ABI but
when cross-compiling success of BTFIDS depends on the default toolchain
ABI.
It's problem independent of this patch - the problem exists both be
From: "Aneesh Kumar K.V"
The type values H_RPTI_TYPE_PRT and H_RPTI_TYPE_PAT indicate
invalidating the caching of process and partition scoped entries
respectively.
Signed-off-by: Aneesh Kumar K.V
Signed-off-by: Bharata B Rao
Reviewed-by: David Gibson
---
arch/powerpc/include/asm/hvcall.h |
This patchset adds support for the new hcall H_RPT_INVALIDATE
and replaces the nested tlb flush calls with this new hcall
if support for the same exists.
Changes in v7:
-
- Fixed a bug where LPID of nested guest was being fetched
wrongly in the process scoped invalidation part of nes
Add a field to mmu_psize_def to store the page size encodings
of H_RPT_INVALIDATE hcall. Initialize this while scanning the radix
AP encodings. This will be used when invalidating with required
page size encoding in the hcall.
Signed-off-by: Bharata B Rao
Reviewed-by: David Gibson
---
arch/powe
Enable support for process-scoped invalidations from nested
guests and partition-scoped invalidations for nested guests.
Process-scoped invalidations for any level of nested guests
are handled by implementing H_RPT_INVALIDATE handler in the
nested guest exit path in L0.
Partition-scoped invalidat
H_RPT_INVALIDATE does two types of TLB invalidations:
1. Process-scoped invalidations for guests when LPCR[GTSE]=0.
This is currently not used in KVM as GTSE is not usually
disabled in KVM.
2. Partition-scoped invalidations that an L1 hypervisor does on
behalf of an L2 guest. This is curr
Now that we have H_RPT_INVALIDATE fully implemented, enable
support for the same via KVM_CAP_PPC_RPT_INVALIDATE KVM capability
Signed-off-by: Bharata B Rao
Reviewed-by: David Gibson
---
Documentation/virt/kvm/api.rst | 18 ++
arch/powerpc/kvm/powerpc.c | 3 +++
include/uapi
In the nested KVM case, replace H_TLB_INVALIDATE by the new hcall
H_RPT_INVALIDATE if available. The availability of this hcall
is determined from "hcall-rpt-invalidate" string in ibm,hypertas-functions
DT property.
Signed-off-by: Bharata B Rao
Reviewed-by: Fabiano Rosas
Reviewed-by: David Gibso
On Wed, May 05, 2021 at 05:23:37PM +0200, Michal Suchánek wrote:
> Hello,
>
> looks like the ABI flags are not correctly applied when cross-compiling.
>
> While building natively success of BTFIDS depends on the kernel ABI but
> when cross-compiling success of BTFIDS depends on the default toolch
On 05/05/21 14:15, Nicholas Piggin wrote:
Commit b1c5356e873c ("KVM: PPC: Convert to the gfn-based MMU notifier
callbacks") causes unmap_gfn_range and age_gfn callbacks to only work
on the first gfn in the range. It also makes the aging callbacks call
into both radix and hash aging functions for
From: Russell Currey
[ Upstream commit 3a72c94ebfb1f171eba0715998010678a09ec796 ]
The rfi_flush and entry_flush selftests work by using the PM_LD_MISS_L1
perf event to count L1D misses. The value of this event has changed
over time:
- Power7 uses 0x400f0
- Power8 and Power9 use both 0x400f0 an
From: Christophe Leroy
[ Upstream commit a4719f5bb6d7dc220bffdc1b9f5ce5eaa5543581 ]
The check of the emergency context initialisation in
vmap_stack_overflow is buggy for the SMP case, as it
compares r1 with 0 while in the SMP case r1 is offseted
by the CPU id.
Instead of fixing it, just perform
From: Vaibhav Jain
[ Upstream commit a5d6a3e73acbd619dd5b7b831762b755f9e2db80 ]
While removing large number of mappings from hash page tables for
large memory systems as soft-lockup is reported because of the time
spent inside htap_remove_mapping() like one below:
watchdog: BUG: soft lockup -
From: Cédric Le Goater
[ Upstream commit e9e16917bc388846163b8566a298a291d71e44c9 ]
The 'chip_id' field of the XIVE CPU structure is used to choose a
target for a source located on the same chip. For that, the XIVE
driver queries the chip identifier from the "ibm,chip-id" property
and compares i
From: Srikar Dronamraju
[ Upstream commit 6980d13f0dd189846887bbbfa43793d9a41768d3 ]
Geethika reported a trace when doing a dlpar CPU add.
[ cut here ]
WARNING: CPU: 152 PID: 1134 at kernel/sched/topology.c:2057
CPU: 152 PID: 1134 Comm: kworker/152:1 Not tainted 5.12.0-r
From: Michael Ellerman
[ Upstream commit ed8029d7b472369a010a1901358567ca3b6dbb0d ]
RCU complains about us calling printk() from an offline CPU:
=
WARNING: suspicious RCU usage
5.12.0-rc7-02874-g7cf90e481cb8 #1 Not tainted
-
kern
From: Alexey Kardashevskiy
[ Upstream commit cc7130bf119add37f36238343a593b71ef6ecc1e ]
The IOMMU table is divided into pools for concurrent mappings and each
pool has a separate spinlock. When taking the ownership of an IOMMU group
to pass through a device to a VM, we lock these spinlocks which
From: Russell Currey
[ Upstream commit 3a72c94ebfb1f171eba0715998010678a09ec796 ]
The rfi_flush and entry_flush selftests work by using the PM_LD_MISS_L1
perf event to count L1D misses. The value of this event has changed
over time:
- Power7 uses 0x400f0
- Power8 and Power9 use both 0x400f0 an
From: Christophe Leroy
[ Upstream commit a4719f5bb6d7dc220bffdc1b9f5ce5eaa5543581 ]
The check of the emergency context initialisation in
vmap_stack_overflow is buggy for the SMP case, as it
compares r1 with 0 while in the SMP case r1 is offseted
by the CPU id.
Instead of fixing it, just perform
From: Vaibhav Jain
[ Upstream commit a5d6a3e73acbd619dd5b7b831762b755f9e2db80 ]
While removing large number of mappings from hash page tables for
large memory systems as soft-lockup is reported because of the time
spent inside htap_remove_mapping() like one below:
watchdog: BUG: soft lockup -
From: Cédric Le Goater
[ Upstream commit e9e16917bc388846163b8566a298a291d71e44c9 ]
The 'chip_id' field of the XIVE CPU structure is used to choose a
target for a source located on the same chip. For that, the XIVE
driver queries the chip identifier from the "ibm,chip-id" property
and compares i
From: Srikar Dronamraju
[ Upstream commit 6980d13f0dd189846887bbbfa43793d9a41768d3 ]
Geethika reported a trace when doing a dlpar CPU add.
[ cut here ]
WARNING: CPU: 152 PID: 1134 at kernel/sched/topology.c:2057
CPU: 152 PID: 1134 Comm: kworker/152:1 Not tainted 5.12.0-r
From: Michael Ellerman
[ Upstream commit ed8029d7b472369a010a1901358567ca3b6dbb0d ]
RCU complains about us calling printk() from an offline CPU:
=
WARNING: suspicious RCU usage
5.12.0-rc7-02874-g7cf90e481cb8 #1 Not tainted
-
kern
From: Alexey Kardashevskiy
[ Upstream commit cc7130bf119add37f36238343a593b71ef6ecc1e ]
The IOMMU table is divided into pools for concurrent mappings and each
pool has a separate spinlock. When taking the ownership of an IOMMU group
to pass through a device to a VM, we lock these spinlocks which
From: Russell Currey
[ Upstream commit 3a72c94ebfb1f171eba0715998010678a09ec796 ]
The rfi_flush and entry_flush selftests work by using the PM_LD_MISS_L1
perf event to count L1D misses. The value of this event has changed
over time:
- Power7 uses 0x400f0
- Power8 and Power9 use both 0x400f0 an
From: Christophe Leroy
[ Upstream commit a4719f5bb6d7dc220bffdc1b9f5ce5eaa5543581 ]
The check of the emergency context initialisation in
vmap_stack_overflow is buggy for the SMP case, as it
compares r1 with 0 while in the SMP case r1 is offseted
by the CPU id.
Instead of fixing it, just perform
From: Vaibhav Jain
[ Upstream commit a5d6a3e73acbd619dd5b7b831762b755f9e2db80 ]
While removing large number of mappings from hash page tables for
large memory systems as soft-lockup is reported because of the time
spent inside htap_remove_mapping() like one below:
watchdog: BUG: soft lockup -
From: Srikar Dronamraju
[ Upstream commit 6980d13f0dd189846887bbbfa43793d9a41768d3 ]
Geethika reported a trace when doing a dlpar CPU add.
[ cut here ]
WARNING: CPU: 152 PID: 1134 at kernel/sched/topology.c:2057
CPU: 152 PID: 1134 Comm: kworker/152:1 Not tainted 5.12.0-r
From: Michael Ellerman
[ Upstream commit ed8029d7b472369a010a1901358567ca3b6dbb0d ]
RCU complains about us calling printk() from an offline CPU:
=
WARNING: suspicious RCU usage
5.12.0-rc7-02874-g7cf90e481cb8 #1 Not tainted
-
kern
From: Alexey Kardashevskiy
[ Upstream commit cc7130bf119add37f36238343a593b71ef6ecc1e ]
The IOMMU table is divided into pools for concurrent mappings and each
pool has a separate spinlock. When taking the ownership of an IOMMU group
to pass through a device to a VM, we lock these spinlocks which
From: Srikar Dronamraju
[ Upstream commit 6980d13f0dd189846887bbbfa43793d9a41768d3 ]
Geethika reported a trace when doing a dlpar CPU add.
[ cut here ]
WARNING: CPU: 152 PID: 1134 at kernel/sched/topology.c:2057
CPU: 152 PID: 1134 Comm: kworker/152:1 Not tainted 5.12.0-r
From: Michael Ellerman
[ Upstream commit ed8029d7b472369a010a1901358567ca3b6dbb0d ]
RCU complains about us calling printk() from an offline CPU:
=
WARNING: suspicious RCU usage
5.12.0-rc7-02874-g7cf90e481cb8 #1 Not tainted
-
kern
From: Alexey Kardashevskiy
[ Upstream commit cc7130bf119add37f36238343a593b71ef6ecc1e ]
The IOMMU table is divided into pools for concurrent mappings and each
pool has a separate spinlock. When taking the ownership of an IOMMU group
to pass through a device to a VM, we lock these spinlocks which
From: Srikar Dronamraju
[ Upstream commit 6980d13f0dd189846887bbbfa43793d9a41768d3 ]
Geethika reported a trace when doing a dlpar CPU add.
[ cut here ]
WARNING: CPU: 152 PID: 1134 at kernel/sched/topology.c:2057
CPU: 152 PID: 1134 Comm: kworker/152:1 Not tainted 5.12.0-r
From: Alexey Kardashevskiy
[ Upstream commit cc7130bf119add37f36238343a593b71ef6ecc1e ]
The IOMMU table is divided into pools for concurrent mappings and each
pool has a separate spinlock. When taking the ownership of an IOMMU group
to pass through a device to a VM, we lock these spinlocks which
From: Michael Ellerman
[ Upstream commit ed8029d7b472369a010a1901358567ca3b6dbb0d ]
RCU complains about us calling printk() from an offline CPU:
=
WARNING: suspicious RCU usage
5.12.0-rc7-02874-g7cf90e481cb8 #1 Not tainted
-
kern
From: Srikar Dronamraju
[ Upstream commit 6980d13f0dd189846887bbbfa43793d9a41768d3 ]
Geethika reported a trace when doing a dlpar CPU add.
[ cut here ]
WARNING: CPU: 152 PID: 1134 at kernel/sched/topology.c:2057
CPU: 152 PID: 1134 Comm: kworker/152:1 Not tainted 5.12.0-r
From: Michael Ellerman
[ Upstream commit ed8029d7b472369a010a1901358567ca3b6dbb0d ]
RCU complains about us calling printk() from an offline CPU:
=
WARNING: suspicious RCU usage
5.12.0-rc7-02874-g7cf90e481cb8 #1 Not tainted
-
kern
From: Alexey Kardashevskiy
[ Upstream commit cc7130bf119add37f36238343a593b71ef6ecc1e ]
The IOMMU table is divided into pools for concurrent mappings and each
pool has a separate spinlock. When taking the ownership of an IOMMU group
to pass through a device to a VM, we lock these spinlocks which
From: Michael Ellerman
[ Upstream commit ed8029d7b472369a010a1901358567ca3b6dbb0d ]
RCU complains about us calling printk() from an offline CPU:
=
WARNING: suspicious RCU usage
5.12.0-rc7-02874-g7cf90e481cb8 #1 Not tainted
-
kern
From: Alexey Kardashevskiy
[ Upstream commit cc7130bf119add37f36238343a593b71ef6ecc1e ]
The IOMMU table is divided into pools for concurrent mappings and each
pool has a separate spinlock. When taking the ownership of an IOMMU group
to pass through a device to a VM, we lock these spinlocks which
From: Alexey Kardashevskiy
[ Upstream commit cc7130bf119add37f36238343a593b71ef6ecc1e ]
The IOMMU table is divided into pools for concurrent mappings and each
pool has a separate spinlock. When taking the ownership of an IOMMU group
to pass through a device to a VM, we lock these spinlocks which
On Tue, Apr 27, 2021 at 4:30 AM Matthieu Baerts
wrote:
>
> Hi,
>
> Thank you for the patch!
>
> On 24/04/2021 13:48, Masahiro Yamada wrote:
> > LANG gives a weak default to each LC_* in case it is not explicitly
> > defined. LC_ALL, if set, overrides all other LC_* variables.
> >
> > LANG < LC
Currently drc_pmem_qeury_stats() generates a dev_err in case
"Enable Performance Information Collection" feature is disabled from
HMC or performance stats are not available for an nvdimm. The error is
of the form below:
papr_scm ibm,persistent-memory:ibm,pmemory@44104001: Failed to query
In case performance stats for an nvdimm are not available, reading the
'perf_stats' sysfs file returns an -ENOENT error. A better approach is
to make the 'perf_stats' file entirely invisible to indicate that
performance stats for an nvdimm are unavailable.
So this patch updates 'papr_nd_attribute_
'rc' is known to be 0 here.
Initialize 'rc' with the expected error code before using it.
While at it, avoid the affectation of 'rc' in a 'if' to make things more
obvious and linux style.
Fixes: f204e0b8ce ("cxl: Driver code for powernv PCIe based cards for userspace
access")
Signed-off-by: Chri
Hi Vaibhav,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on powerpc/next]
[also build test WARNING on v5.12 next-20210505]
[cannot apply to scottwood/next mpe/next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting
Hi all,
On Wed, 5 May 2021 11:39:59 +1000 Stephen Rothwell
wrote:
>
> Today's linux-next merge of the akpm-current tree got a conflict in:
>
> arch/powerpc/Kconfig
>
> between commit:
>
> c6b05f4e233c ("powerpc/kconfig: Restore alphabetic order of the selects
> under CONFIG_PPC")
>
> fr
Document the fsl,i2c-erratum-a004447 flag which indicates the presence
of an i2c erratum on some QorIQ SoCs.
Signed-off-by: Chris Packham
---
Documentation/devicetree/bindings/i2c/i2c-mpc.yaml | 7 +++
1 file changed, 7 insertions(+)
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mp
The P2040/P2041 has an erratum where the i2c recovery scheme
documented in the reference manual (and currently implemented
in the i2c-mpc.c driver) does not work. The errata document
provides an alternative that does work. This series implements
that alternative and uses a property in the devicetre
The P2040/P2041 has an erratum where the normal i2c recovery mechanism
does not work. Implement the alternative recovery mechanism documented
in the P2040 Chip Errata Rev Q.
Signed-off-by: Chris Packham
---
drivers/i2c/busses/i2c-mpc.c | 88 +++-
1 file changed, 8
The i2c controllers on the P2040/P2041 have an erratum where the
documented scheme for i2c bus recovery will not work (A-004447). A
different mechanism is needed which is documented in the P2040 Chip
Errata Rev Q (latest available at the time of writing).
Signed-off-by: Chris Packham
---
arch/po
Fix the following coccicheck warning:
./sound/soc/fsl/fsl_xcvr.c:739:2-3: Unneeded semicolon
Signed-off-by: Wan Jiabing
---
sound/soc/fsl/fsl_xcvr.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/soc/fsl/fsl_xcvr.c b/sound/soc/fsl/fsl_xcvr.c
index 6cb558165848..df7c18
On 6/5/21 5:38 am, Christophe JAILLET wrote:
'rc' is known to be 0 here.
Initialize 'rc' with the expected error code before using it.
I would prefer:
"In cxl_add_chardev(), if the call to device_create() fails, we print
the error message before 'rc' is set correctly, and therefore always
pr
Adding more Strict RWX support on powerpc, in particular Strict Module RWX.
Thanks for all of the feedback everyone.
It is now rebased on linux-next + powerpc/64s/radix: Enable huge vmalloc
mappings
(https://lore.kernel.org/linuxppc-dev/20210503091755.613393-1-npig...@gmail.com/)
For reference th
From: Russell Currey
The set_memory_{ro/rw/nx/x}() functions are required for
STRICT_MODULE_RWX, and are generally useful primitives to have. This
implementation is designed to be generic across powerpc's many MMUs.
It's possible that this could be optimised to be faster for specific
MMUs.
This
setup_text_poke_area() is a late init call so it runs before
mark_rodata_ro() and after the init calls. This lets all the init code
patching simply write to their locations. In the future, kprobes is
going to allocate its instruction pages RO which means they will need
setup_text__poke_area() to ha
From: Russell Currey
Add the arch specific insn page allocator for powerpc. This allocates
ROX pages if STRICT_KERNEL_RWX is enabled. These pages are only written
to with patch_instruction() which is able to write RO pages.
Reviewed-by: Daniel Axtens
Signed-off-by: Russell Currey
Signed-off-by
Commit 74451e66d516 ("bpf: make jited programs visible in traces") added
a default bpf_jit_free() implementation. Powerpc did not use the default
bpf_jit_free() as powerpc did not set the images read-only. The default
bpf_jit_free() called bpf_jit_binary_unlock_ro() is why it could not be
used for
Add the necessary call to bpf_jit_binary_lock_ro() to remove write and
add exec permissions to the JIT image after it has finished being
written.
Without CONFIG_STRICT_MODULE_RWX the image will be writable and
executable until the call to bpf_jit_binary_lock_ro().
Signed-off-by: Jordan Niethe
--
From: Russell Currey
To enable strict module RWX on powerpc, set:
CONFIG_STRICT_MODULE_RWX=y
You should also have CONFIG_STRICT_KERNEL_RWX=y set to have any real
security benefit.
ARCH_HAS_STRICT_MODULE_RWX is set to require ARCH_HAS_STRICT_KERNEL_RWX.
This is due to a quirk in arch/Kconfi
From: Christophe Leroy
In addition to the set_memory_xx() functions which allows to change
the memory attributes of not (yet) used memory regions, implement a
set_memory_attr() function to:
- set the final memory protection after init on currently used
kernel regions.
- enable/disable kernel memo
From: Christophe Leroy
Use set_memory_attr() instead of the PPC32 specific change_page_attr()
change_page_attr() was checking that the address was not mapped by
blocks and was handling highmem, but that's unneeded because the
affected pages can't be in highmem and block mapping verification
is a
On Thu, May 6, 2021 at 10:26 AM Wan Jiabing wrote:
>
> Fix the following coccicheck warning:
>
> ./sound/soc/fsl/fsl_xcvr.c:739:2-3: Unneeded semicolon
>
> Signed-off-by: Wan Jiabing
Acked-by: Shengjiu Wang
> ---
> sound/soc/fsl/fsl_xcvr.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(
When live patching with STRICT_KERNEL_RWX a mapping is installed at a
"patching address" with temporary write permissions. Provide a
LKDTM-only accessor function for this address in preparation for a LKDTM
test which attempts to "hijack" this mapping by writing to it from
another CPU.
Signed-off-b
When live patching with STRICT_KERNEL_RWX the CPU doing the patching
must temporarily remap the page(s) containing the patch site with +W
permissions. While this temporary mapping is in use, another CPU could
write to the same mapping and maliciously alter kernel text. Implement a
LKDTM test to att
Code patching on powerpc with a STRICT_KERNEL_RWX uses a userspace
address in a temporary mm now. Use __put_user() to avoid write failures
due to KUAP when attempting a "hijack" on the patching address.
Signed-off-by: Christopher M. Riedl
---
drivers/misc/lkdtm/perms.c | 9 -
1 file chan
When live patching with STRICT_KERNEL_RWX a mapping is installed at a
"patching address" with temporary write permissions. Provide a
LKDTM-only accessor function for this address in preparation for a LKDTM
test which attempts to "hijack" this mapping by writing to it from
another CPU.
Signed-off-b
A previous commit implemented an LKDTM test on powerpc to exploit the
temporary mapping established when patching code with STRICT_KERNEL_RWX
enabled. Extend the test to work on x86_64 as well.
Signed-off-by: Christopher M. Riedl
---
drivers/misc/lkdtm/perms.c | 29 ++---
Switching to a different mm with Hash translation causes SLB entries to
be preloaded from the current thread_info. This reduces SLB faults, for
example when threads share a common mm but operate on different address
ranges.
Preloading entries from the thread_info struct may not always be
appropria
When code patching a STRICT_KERNEL_RWX kernel the page containing the
address to be patched is temporarily mapped as writeable. Currently, a
per-cpu vmalloc patch area is used for this purpose. While the patch
area is per-cpu, the temporary page mapping is inserted into the kernel
page tables for t
Powerpc allows for multiple CPUs to patch concurrently. When patching
with STRICT_KERNEL_RWX a single patching_mm is allocated for use by all
CPUs for the few times that patching occurs. Use a spinlock to protect
the patching_mm from concurrent use.
Modify patch_instruction() to acquire the lock,
With Book3s64 Hash translation, manually inserting a PTE requires
updating the Linux PTE, inserting a SLB entry, and inserting the hashed
page. The first is handled via the usual kernel abstractions, the second
requires slb_allocate_user() which is currently 'static', and the third
is available via
x86 supports the notion of a temporary mm which restricts access to
temporary PTEs to a single CPU. A temporary mm is useful for situations
where a CPU needs to perform sensitive operations (such as patching a
STRICT_KERNEL_RWX kernel) requiring temporary mappings without exposing
said mappings to
Now that patching requires a lock to prevent concurrent access to
patching_mm, every call to patch_instruction() acquires and releases a
spinlock. There are several places where patch_instruction() is called
in a loop. Convert these to acquire the lock once before the loop, call
patch_instruction_u
When compiled with CONFIG_STRICT_KERNEL_RWX, the kernel must create
temporary mappings when patching itself. These mappings temporarily
override the strict RWX text protections to permit a write. Currently,
powerpc allocates a per-CPU VM area for patching. Patching occurs as
follows:
1. Ma
The entry flush mitigation can be enabled/disabled at runtime via a
debugfs file (entry_flush), which causes the kernel to patch itself to
enable/disable the relevant mitigations.
However depending on which mitigation we're using, it may not be safe to
do that patching while other CPUs are active.
The STF (store-to-load forwarding) barrier mitigation can be
enabled/disabled at runtime via a debugfs file (stf_barrier), which
causes the kernel to patch itself to enable/disable the relevant
mitigations.
However depending on which mitigation we're using, it may not be safe to
do that patching w
Excerpts from Sean Christopherson's message of May 6, 2021 1:52 am:
> On Wed, May 05, 2021, Nicholas Piggin wrote:
>> Commit b1c5356e873c ("KVM: PPC: Convert to the gfn-based MMU notifier
>> callbacks") causes unmap_gfn_range and age_gfn callbacks to only work
>> on the first gfn in the range. It a
On Thu, May 06, 2021 at 12:46:06AM +0530, Vaibhav Jain wrote:
> Currently drc_pmem_qeury_stats() generates a dev_err in case
> "Enable Performance Information Collection" feature is disabled from
> HMC or performance stats are not available for an nvdimm. The error is
> of the form below:
>
> papr
Vaibhav Jain writes:
> In case performance stats for an nvdimm are not available, reading the
> 'perf_stats' sysfs file returns an -ENOENT error. A better approach is
> to make the 'perf_stats' file entirely invisible to indicate that
> performance stats for an nvdimm are unavailable.
>
> So this
Excerpts from Bharata B Rao's message of May 6, 2021 1:46 am:
> H_RPT_INVALIDATE does two types of TLB invalidations:
>
> 1. Process-scoped invalidations for guests when LPCR[GTSE]=0.
>This is currently not used in KVM as GTSE is not usually
>disabled in KVM.
> 2. Partition-scoped invalida
Le 05/05/2021 à 14:43, Christian Zigotzky a écrit :
On 04 May 2021 at 05:17pm, Christophe Leroy wrote:
Le 04/05/2021 à 16:59, Christian Zigotzky a écrit :
On 04 May 2021 at 04:41pm Christophe Leroy wrote:
Le 04/05/2021 à 13:02, Christian Zigotzky a écrit :
On 04 May 2021 at 12:07pm, Christ
Excerpts from Bharata B Rao's message of May 6, 2021 1:46 am:
> Enable support for process-scoped invalidations from nested
> guests and partition-scoped invalidations for nested guests.
>
> Process-scoped invalidations for any level of nested guests
> are handled by implementing H_RPT_INVALIDATE
On Thu, May 06, 2021 at 03:45:21PM +1000, Nicholas Piggin wrote:
> Excerpts from Bharata B Rao's message of May 6, 2021 1:46 am:
> >
> > +static long kvmppc_h_rpt_invalidate(struct kvm_vcpu *vcpu,
> > + unsigned long id, unsigned long target,
> > +
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