<feed xmlns='http://www.w3.org/2005/Atom'>
<title>blaster4385/linux-IllusionX/arch/powerpc/kexec, branch v6.12.1</title>
<subtitle>Linux kernel with personal config changes for arch linux</subtitle>
<id>http://git.tablaster.dev/blaster4385/linux-IllusionX/atom?h=v6.12.1</id>
<link rel='self' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/atom?h=v6.12.1'/>
<link rel='alternate' type='text/html' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/'/>
<updated>2024-07-20T04:00:33Z</updated>
<entry>
<title>Merge tag 'powerpc-6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux</title>
<updated>2024-07-20T04:00:33Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-07-20T04:00:33Z</published>
<link rel='alternate' type='text/html' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/commit/?id=3c3ff7be9729959699eb6cbc7fd7303566d74069'/>
<id>urn:sha1:3c3ff7be9729959699eb6cbc7fd7303566d74069</id>
<content type='text'>
Pull powerpc updates from Michael Ellerman:

 - Remove support for 40x CPUs &amp; platforms

 - Add support to the 64-bit BPF JIT for cpu v4 instructions

 - Fix PCI hotplug driver crash on powernv

 - Fix doorbell emulation for KVM on PAPR guests (nestedv2)

 - Fix KVM nested guest handling of some less used SPRs

 - Online NUMA nodes with no CPU/memory if they have a PCI device
   attached

 - Reduce memory overhead of enabling kfence on 64-bit Radix MMU kernels

 - Reimplement the iommu table_group_ops for pseries for VFIO SPAPR TCE

Thanks to: Anjali K, Artem Savkov, Athira Rajeev, Breno Leitao, Brian
King, Celeste Liu, Christophe Leroy, Esben Haabendal, Gaurav Batra,
Gautam Menghani, Haren Myneni, Hari Bathini, Jeff Johnson, Krishna
Kumar, Krzysztof Kozlowski, Nathan Lynch, Nicholas Piggin, Nick Bowler,
Nilay Shroff, Rob Herring (Arm), Shawn Anastasio, Shivaprasad G Bhat,
Sourabh Jain, Srikar Dronamraju, Timothy Pearson, Uwe Kleine-König, and
Vaibhav Jain.

* tag 'powerpc-6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (57 commits)
  Documentation/powerpc: Mention 40x is removed
  powerpc: Remove 40x leftovers
  macintosh/therm_windtunnel: fix module unload.
  powerpc: Check only single values are passed to CPU/MMU feature checks
  powerpc/xmon: Fix disassembly CPU feature checks
  powerpc: Drop clang workaround for builtin constant checks
  powerpc64/bpf: jit support for signed division and modulo
  powerpc64/bpf: jit support for sign extended mov
  powerpc64/bpf: jit support for sign extended load
  powerpc64/bpf: jit support for unconditional byte swap
  powerpc64/bpf: jit support for 32bit offset jmp instruction
  powerpc/pci: Hotplug driver bridge support
  pci/hotplug/pnv_php: Fix hotplug driver crash on Powernv
  powerpc/configs: Update defconfig with now user-visible CONFIG_FSL_IFC
  powerpc: add missing MODULE_DESCRIPTION() macros
  macintosh/mac_hid: add MODULE_DESCRIPTION()
  KVM: PPC: add missing MODULE_DESCRIPTION() macros
  powerpc/kexec: Use of_property_read_reg()
  powerpc/64s/radix/kfence: map __kfence_pool at page granularity
  powerpc/pseries/iommu: Define spapr_tce_table_group_ops only with CONFIG_IOMMU_API
  ...
</content>
</entry>
<entry>
<title>powerpc/kexec: Use of_property_read_reg()</title>
<updated>2024-07-04T11:55:18Z</updated>
<author>
<name>Rob Herring (Arm)</name>
<email>robh@kernel.org</email>
</author>
<published>2024-07-02T21:03:44Z</published>
<link rel='alternate' type='text/html' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/commit/?id=cf08b628cd146a3cb597999f4d4dc590068bf011'/>
<id>urn:sha1:cf08b628cd146a3cb597999f4d4dc590068bf011</id>
<content type='text'>
Replace open-coded parsing of "reg" property with
of_property_read_reg().

Signed-off-by: Rob Herring (Arm) &lt;robh@kernel.org&gt;
[mpe: Rename end to size, add comment to the bail out case]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240702210344.722364-1-robh@kernel.org

</content>
</entry>
<entry>
<title>powerpc/pseries: Fix scv instruction crash with kexec</title>
<updated>2024-06-28T12:05:44Z</updated>
<author>
<name>Nicholas Piggin</name>
<email>npiggin@gmail.com</email>
</author>
<published>2024-06-25T13:40:47Z</published>
<link rel='alternate' type='text/html' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/commit/?id=21a741eb75f80397e5f7d3739e24d7d75e619011'/>
<id>urn:sha1:21a741eb75f80397e5f7d3739e24d7d75e619011</id>
<content type='text'>
kexec on pseries disables AIL (reloc_on_exc), required for scv
instruction support, before other CPUs have been shut down. This means
they can execute scv instructions after AIL is disabled, which causes an
interrupt at an unexpected entry location that crashes the kernel.

Change the kexec sequence to disable AIL after other CPUs have been
brought down.

As a refresher, the real-mode scv interrupt vector is 0x17000, and the
fixed-location head code probably couldn't easily deal with implementing
such high addresses so it was just decided not to support that interrupt
at all.

Fixes: 7fa95f9adaee ("powerpc/64s: system call support for scv/rfscv instructions")
Cc: stable@vger.kernel.org # v5.9+
Reported-by: Sourabh Jain &lt;sourabhjain@linux.ibm.com&gt;
Closes: https://lore.kernel.org/3b4b2943-49ad-4619-b195-bc416f1d1409@linux.ibm.com
Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Tested-by: Gautam Menghani &lt;gautam@linux.ibm.com&gt;
Tested-by: Sourabh Jain &lt;sourabhjain@linux.ibm.com&gt;
Link: https://msgid.link/20240625134047.298759-1-npiggin@gmail.com
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</content>
</entry>
<entry>
<title>powerpc/kexec_file: fix cpus node update to FDT</title>
<updated>2024-06-17T12:48:45Z</updated>
<author>
<name>Sourabh Jain</name>
<email>sourabhjain@linux.ibm.com</email>
</author>
<published>2024-05-10T10:22:35Z</published>
<link rel='alternate' type='text/html' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/commit/?id=932bed41217059638c78a75411b7893b121d2162'/>
<id>urn:sha1:932bed41217059638c78a75411b7893b121d2162</id>
<content type='text'>
While updating the cpus node, commit 40c753993e3a ("powerpc/kexec_file:
 Use current CPU info while setting up FDT") first deletes all subnodes
under the /cpus node. However, while adding sub-nodes back, it missed
adding cpus subnodes whose device_type != "cpu", such as l2-cache*,
l3-cache*, ibm,powerpc-cpu-features.

Fix this by only deleting cpus sub-nodes of device_type == "cpus" and
then adding all available nodes with device_type == "cpu".

Fixes: 40c753993e3a ("powerpc/kexec_file: Use current CPU info while setting up FDT")
Signed-off-by: Sourabh Jain &lt;sourabhjain@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240510102235.2269496-3-sourabhjain@linux.ibm.com

</content>
</entry>
<entry>
<title>powerpc/kexec_file: fix extra size calculation for kexec FDT</title>
<updated>2024-06-17T12:48:45Z</updated>
<author>
<name>Sourabh Jain</name>
<email>sourabhjain@linux.ibm.com</email>
</author>
<published>2024-05-10T10:22:34Z</published>
<link rel='alternate' type='text/html' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/commit/?id=0d3ff067331ef84e7e7f49537d768881042ed5ba'/>
<id>urn:sha1:0d3ff067331ef84e7e7f49537d768881042ed5ba</id>
<content type='text'>
While setting up the FDT for kexec, CPU nodes that are added after the
system boots and reserved memory ranges are incorporated into the
initial_boot_params (base FDT).

However, they are not taken into account when determining the additional
size needed for the kexec FDT. As a result, kexec fails to load,
generating the following error:

[1116.774451] Error updating memory reserve map: FDT_ERR_NOSPACE
kexec_file_load failed: No such process

Therefore, consider the extra size for CPU nodes added post-system boot
and reserved memory ranges while preparing the kexec FDT.

While adding a new parameter to the setup_new_fdt_ppc64 function, it was
noticed that there were a couple of unused parameters, so they were
removed.

Signed-off-by: Sourabh Jain &lt;sourabhjain@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240510102235.2269496-2-sourabhjain@linux.ibm.com

</content>
</entry>
<entry>
<title>powerpc/crash: remove unnecessary NULL check before kvfree()</title>
<updated>2024-05-03T02:20:50Z</updated>
<author>
<name>Sourabh Jain</name>
<email>sourabhjain@linux.ibm.com</email>
</author>
<published>2024-05-02T18:20:40Z</published>
<link rel='alternate' type='text/html' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/commit/?id=9803af291162dbca4b9773586a3f5c392f0dd974'/>
<id>urn:sha1:9803af291162dbca4b9773586a3f5c392f0dd974</id>
<content type='text'>
Fix the following coccicheck build warning:

arch/powerpc/kexec/crash.c:488:2-8: WARNING: NULL check before some
freeing functions is not needed.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: https://lore.kernel.org/oe-kbuild-all/202404261048.skfV5DDB-lkp@intel.com/
Signed-off-by: Sourabh Jain &lt;sourabhjain@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240502182040.774759-1-sourabhjain@linux.ibm.com

</content>
</entry>
<entry>
<title>powerpc/crash: add crash memory hotplug support</title>
<updated>2024-04-23T05:00:04Z</updated>
<author>
<name>Sourabh Jain</name>
<email>sourabhjain@linux.ibm.com</email>
</author>
<published>2024-03-26T05:54:13Z</published>
<link rel='alternate' type='text/html' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/commit/?id=849599b702ef8977fcd5b2f27c61ef773c42bb88'/>
<id>urn:sha1:849599b702ef8977fcd5b2f27c61ef773c42bb88</id>
<content type='text'>
Extend the arch crash hotplug handler, as introduced by the patch title
("powerpc: add crash CPU hotplug support"), to also support memory
add/remove events.

Elfcorehdr describes the memory of the crash kernel to capture the
kernel; hence, it needs to be updated if memory resources change due to
memory add/remove events. Therefore, arch_crash_handle_hotplug_event()
is updated to recreate the elfcorehdr and replace it with the previous
one on memory add/remove events.

The memblock list is used to prepare the elfcorehdr. In the case of
memory hot remove, the memblock list is updated after the arch crash
hotplug handler is triggered, as depicted in Figure 1. Thus, the
hot-removed memory is explicitly removed from the crash memory ranges
to ensure that the memory ranges added to elfcorehdr do not include the
hot-removed memory.

    Memory remove
          |
          v
    Offline pages
          |
          v
 Initiate memory notify call &lt;----&gt; crash hotplug handler
 chain for MEM_OFFLINE event
          |
          v
 Update memblock list

 	Figure 1

There are two system calls, `kexec_file_load` and `kexec_load`, used to
load the kdump image. A few changes have been made to ensure that the
kernel can safely update the elfcorehdr component of the kdump image for
both system calls.

For the kexec_file_load syscall, kdump image is prepared in the kernel.
To support an increasing number of memory regions, the elfcorehdr is
built with extra buffer space to ensure that it can accommodate
additional memory ranges in future.

For the kexec_load syscall, the elfcorehdr is updated only if the
KEXEC_CRASH_HOTPLUG_SUPPORT kexec flag is passed to the kernel by the
kexec tool. Passing this flag to the kernel indicates that the
elfcorehdr is built to accommodate additional memory ranges and the
elfcorehdr segment is not considered for SHA calculation, making it safe
to update.

The changes related to this feature are kept under the CRASH_HOTPLUG
config, and it is enabled by default.

Signed-off-by: Sourabh Jain &lt;sourabhjain@linux.ibm.com&gt;
Acked-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240326055413.186534-7-sourabhjain@linux.ibm.com

</content>
</entry>
<entry>
<title>powerpc/crash: add crash CPU hotplug support</title>
<updated>2024-04-23T05:00:04Z</updated>
<author>
<name>Sourabh Jain</name>
<email>sourabhjain@linux.ibm.com</email>
</author>
<published>2024-03-26T05:54:12Z</published>
<link rel='alternate' type='text/html' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/commit/?id=b741092d59761b98781fcb4f3f521312ed8d5006'/>
<id>urn:sha1:b741092d59761b98781fcb4f3f521312ed8d5006</id>
<content type='text'>
Due to CPU/Memory hotplug or online/offline events, the elfcorehdr
(which describes the CPUs and memory of the crashed kernel) and FDT
(Flattened Device Tree) of kdump image becomes outdated. Consequently,
attempting dump collection with an outdated elfcorehdr or FDT can lead
to failed or inaccurate dump collection.

Going forward, CPU hotplug or online/offline events are referred as
CPU/Memory add/remove events.

The current solution to address the above issue involves monitoring the
CPU/Memory add/remove events in userspace using udev rules and whenever
there are changes in CPU and memory resources, the entire kdump image
is loaded again. The kdump image includes kernel, initrd, elfcorehdr,
FDT, purgatory. Given that only elfcorehdr and FDT get outdated due to
CPU/Memory add/remove events, reloading the entire kdump image is
inefficient. More importantly, kdump remains inactive for a substantial
amount of time until the kdump reload completes.

To address the aforementioned issue, commit 247262756121 ("crash: add
generic infrastructure for crash hotplug support") added a generic
infrastructure that allows architectures to selectively update the kdump
image component during CPU or memory add/remove events within the kernel
itself.

In the event of a CPU or memory add/remove events, the generic crash
hotplug event handler, `crash_handle_hotplug_event()`, is triggered. It
then acquires the necessary locks to update the kdump image and invokes
the architecture-specific crash hotplug handler,
`arch_crash_handle_hotplug_event()`, to update the required kdump image
components.

This patch adds crash hotplug handler for PowerPC and enable support to
update the kdump image on CPU add/remove events. Support for memory
add/remove events is added in a subsequent patch with the title
"powerpc: add crash memory hotplug support"

As mentioned earlier, only the elfcorehdr and FDT kdump image components
need to be updated in the event of CPU or memory add/remove events.
However, on PowerPC architecture crash hotplug handler only updates the
FDT to enable crash hotplug support for CPU add/remove events. Here's
why.

The elfcorehdr on PowerPC is built with possible CPUs, and thus, it does
not need an update on CPU add/remove events. On the other hand, the FDT
needs to be updated on CPU add events to include the newly added CPU. If
the FDT is not updated and the kernel crashes on a newly added CPU, the
kdump kernel will fail to boot due to the unavailability of the crashing
CPU in the FDT. During the early boot, it is expected that the boot CPU
must be a part of the FDT; otherwise, the kernel will raise a BUG and
fail to boot. For more information, refer to commit 36ae37e3436b0
("powerpc: Make boot_cpuid common between 32 and 64-bit"). Since it is
okay to have an offline CPU in the kdump FDT, no action is taken in case
of CPU removal.

There are two system calls, `kexec_file_load` and `kexec_load`, used to
load the kdump image. Few changes have been made to ensure kernel can
safely update the FDT of kdump image loaded using both system calls.

For kexec_file_load syscall the kdump image is prepared in kernel. So to
support an increasing number of CPUs, the FDT is constructed with extra
buffer space to ensure it can accommodate a possible number of CPU
nodes. Additionally, a call to fdt_pack (which trims the unused space
once the FDT is prepared) is avoided if this feature is enabled.

For the kexec_load syscall, the FDT is updated only if the
KEXEC_CRASH_HOTPLUG_SUPPORT kexec flag is passed to the kernel by
userspace (kexec tools). When userspace passes this flag to the kernel,
it indicates that the FDT is built to accommodate possible CPUs, and the
FDT segment is excluded from SHA calculation, making it safe to update.

The changes related to this feature are kept under the CRASH_HOTPLUG
config, and it is enabled by default.

Signed-off-by: Sourabh Jain &lt;sourabhjain@linux.ibm.com&gt;
Acked-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240326055413.186534-6-sourabhjain@linux.ibm.com

</content>
</entry>
<entry>
<title>powerpc/kexec: make the update_cpus_node() function public</title>
<updated>2024-04-23T04:59:51Z</updated>
<author>
<name>Sourabh Jain</name>
<email>sourabhjain@linux.ibm.com</email>
</author>
<published>2024-03-26T05:54:11Z</published>
<link rel='alternate' type='text/html' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/commit/?id=0857beff9c1ec8bb421a8b7a721da0f34cc886c0'/>
<id>urn:sha1:0857beff9c1ec8bb421a8b7a721da0f34cc886c0</id>
<content type='text'>
Move the update_cpus_node() from kexec/{file_load_64.c =&gt; core_64.c}
to allow other kexec components to use it.

Later in the series, this function is used for in-kernel updates
to the kdump image during CPU/memory hotplug or online/offline events for
both kexec_load and kexec_file_load syscalls.

No functional changes are intended.

Signed-off-by: Sourabh Jain &lt;sourabhjain@linux.ibm.com&gt;
Acked-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240326055413.186534-5-sourabhjain@linux.ibm.com
</content>
</entry>
<entry>
<title>powerpc/kexec: move *_memory_ranges functions to ranges.c</title>
<updated>2024-04-23T04:59:01Z</updated>
<author>
<name>Sourabh Jain</name>
<email>sourabhjain@linux.ibm.com</email>
</author>
<published>2024-03-26T05:54:10Z</published>
<link rel='alternate' type='text/html' href='http://git.tablaster.dev/blaster4385/linux-IllusionX/commit/?id=f5f0da5a7b18fab383bac92044fd8f4f288c9d38'/>
<id>urn:sha1:f5f0da5a7b18fab383bac92044fd8f4f288c9d38</id>
<content type='text'>
Move the following functions form kexec/{file_load_64.c =&gt; ranges.c} and
make them public so that components other than KEXEC_FILE can also use
these functions.
1. get_exclude_memory_ranges
2. get_reserved_memory_ranges
3. get_crash_memory_ranges
4. get_usable_memory_ranges

Later in the series get_crash_memory_ranges function is utilized for
in-kernel updates to kdump image during CPU/Memory hotplug or
online/offline events for both kexec_load and kexec_file_load syscalls.

Since the above functions are moved to ranges.c, some of the helper
functions in ranges.c are no longer required to be public. Mark them as
static and removed them from kexec_ranges.h header file.

Finally, remove the CONFIG_KEXEC_FILE build dependency for range.c
because it is required for other config, such as CONFIG_CRASH_DUMP.

No functional changes are intended.

Signed-off-by: Sourabh Jain &lt;sourabhjain@linux.ibm.com&gt;
Acked-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240326055413.186534-4-sourabhjain@linux.ibm.com

</content>
</entry>
</feed>
