<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch/powerpc/net, branch v5.18</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>Merge tag 'powerpc-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux</title>
<updated>2022-03-25T16:39:36+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-03-25T16:39:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1f1c153e406a7375ae0fc3d6000b64e7ba27cf8a'/>
<id>1f1c153e406a7375ae0fc3d6000b64e7ba27cf8a</id>
<content type='text'>
Pull powerpc updates from Michael Ellerman:
 "Livepatch support for 32-bit is probably the standout new feature,
  otherwise mostly just lots of bits and pieces all over the board.

  There's a series of commits cleaning up function descriptor handling,
  which touches a few other arches as well as LKDTM. It has acks from
  Arnd, Kees and Helge.

  Summary:

   - Enforce kernel RO, and implement STRICT_MODULE_RWX for 603.

   - Add support for livepatch to 32-bit.

   - Implement CONFIG_DYNAMIC_FTRACE_WITH_ARGS.

   - Merge vdso64 and vdso32 into a single directory.

   - Fix build errors with newer binutils.

   - Add support for UADDR64 relocations, which are emitted by some
     toolchains. This allows powerpc to build with the latest lld.

   - Fix (another) potential userspace r13 corruption in transactional
     memory handling.

   - Cleanups of function descriptor handling &amp; related fixes to LKDTM.

  Thanks to Abdul Haleem, Alexey Kardashevskiy, Anders Roxell, Aneesh
  Kumar K.V, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Bhaskar
  Chowdhury, Cédric Le Goater, Chen Jingwen, Christophe JAILLET,
  Christophe Leroy, Corentin Labbe, Daniel Axtens, Daniel Henrique
  Barboza, David Dai, Fabiano Rosas, Ganesh Goudar, Guo Zhengkui, Hangyu
  Hua, Haren Myneni, Hari Bathini, Igor Zhbanov, Jakob Koschel, Jason
  Wang, Jeremy Kerr, Joachim Wiberg, Jordan Niethe, Julia Lawall, Kajol
  Jain, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mamatha Inamdar,
  Maxime Bizon, Maxim Kiselev, Maxim Kochetkov, Michal Suchanek,
  Nageswara R Sastry, Nathan Lynch, Naveen N. Rao, Nicholas Piggin,
  Nour-eddine Taleb, Paul Menzel, Ping Fang, Pratik R. Sampat, Randy
  Dunlap, Ritesh Harjani, Rohan McLure, Russell Currey, Sachin Sant,
  Segher Boessenkool, Shivaprasad G Bhat, Sourabh Jain, Thierry Reding,
  Tobias Waldekranz, Tyrel Datwyler, Vaibhav Jain, Vladimir Oltean,
  Wedson Almeida Filho, and YueHaibing"

* tag 'powerpc-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits)
  powerpc/pseries: Fix use after free in remove_phb_dynamic()
  powerpc/time: improve decrementer clockevent processing
  powerpc/time: Fix KVM host re-arming a timer beyond decrementer range
  powerpc/tm: Fix more userspace r13 corruption
  powerpc/xive: fix return value of __setup handler
  powerpc/64: Add UADDR64 relocation support
  powerpc: 8xx: fix a return value error in mpc8xx_pic_init
  powerpc/ps3: remove unneeded semicolons
  powerpc/64: Force inlining of prevent_user_access() and set_kuap()
  powerpc/bitops: Force inlining of fls()
  powerpc: declare unmodified attribute_group usages const
  powerpc/spufs: Fix build warning when CONFIG_PROC_FS=n
  powerpc/secvar: fix refcount leak in format_show()
  powerpc/64e: Tie PPC_BOOK3E_64 to PPC_FSL_BOOK3E
  powerpc: Move C prototypes out of asm-prototypes.h
  powerpc/kexec: Declare kexec_paca static
  powerpc/smp: Declare current_set static
  powerpc: Cleanup asm-prototypes.c
  powerpc/ftrace: Use STK_GOT in ftrace_mprofile.S
  powerpc/ftrace: Regroup PPC64 specific operations in ftrace_mprofile.S
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull powerpc updates from Michael Ellerman:
 "Livepatch support for 32-bit is probably the standout new feature,
  otherwise mostly just lots of bits and pieces all over the board.

  There's a series of commits cleaning up function descriptor handling,
  which touches a few other arches as well as LKDTM. It has acks from
  Arnd, Kees and Helge.

  Summary:

   - Enforce kernel RO, and implement STRICT_MODULE_RWX for 603.

   - Add support for livepatch to 32-bit.

   - Implement CONFIG_DYNAMIC_FTRACE_WITH_ARGS.

   - Merge vdso64 and vdso32 into a single directory.

   - Fix build errors with newer binutils.

   - Add support for UADDR64 relocations, which are emitted by some
     toolchains. This allows powerpc to build with the latest lld.

   - Fix (another) potential userspace r13 corruption in transactional
     memory handling.

   - Cleanups of function descriptor handling &amp; related fixes to LKDTM.

  Thanks to Abdul Haleem, Alexey Kardashevskiy, Anders Roxell, Aneesh
  Kumar K.V, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Bhaskar
  Chowdhury, Cédric Le Goater, Chen Jingwen, Christophe JAILLET,
  Christophe Leroy, Corentin Labbe, Daniel Axtens, Daniel Henrique
  Barboza, David Dai, Fabiano Rosas, Ganesh Goudar, Guo Zhengkui, Hangyu
  Hua, Haren Myneni, Hari Bathini, Igor Zhbanov, Jakob Koschel, Jason
  Wang, Jeremy Kerr, Joachim Wiberg, Jordan Niethe, Julia Lawall, Kajol
  Jain, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mamatha Inamdar,
  Maxime Bizon, Maxim Kiselev, Maxim Kochetkov, Michal Suchanek,
  Nageswara R Sastry, Nathan Lynch, Naveen N. Rao, Nicholas Piggin,
  Nour-eddine Taleb, Paul Menzel, Ping Fang, Pratik R. Sampat, Randy
  Dunlap, Ritesh Harjani, Rohan McLure, Russell Currey, Sachin Sant,
  Segher Boessenkool, Shivaprasad G Bhat, Sourabh Jain, Thierry Reding,
  Tobias Waldekranz, Tyrel Datwyler, Vaibhav Jain, Vladimir Oltean,
  Wedson Almeida Filho, and YueHaibing"

* tag 'powerpc-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits)
  powerpc/pseries: Fix use after free in remove_phb_dynamic()
  powerpc/time: improve decrementer clockevent processing
  powerpc/time: Fix KVM host re-arming a timer beyond decrementer range
  powerpc/tm: Fix more userspace r13 corruption
  powerpc/xive: fix return value of __setup handler
  powerpc/64: Add UADDR64 relocation support
  powerpc: 8xx: fix a return value error in mpc8xx_pic_init
  powerpc/ps3: remove unneeded semicolons
  powerpc/64: Force inlining of prevent_user_access() and set_kuap()
  powerpc/bitops: Force inlining of fls()
  powerpc: declare unmodified attribute_group usages const
  powerpc/spufs: Fix build warning when CONFIG_PROC_FS=n
  powerpc/secvar: fix refcount leak in format_show()
  powerpc/64e: Tie PPC_BOOK3E_64 to PPC_FSL_BOOK3E
  powerpc: Move C prototypes out of asm-prototypes.h
  powerpc/kexec: Declare kexec_paca static
  powerpc/smp: Declare current_set static
  powerpc: Cleanup asm-prototypes.c
  powerpc/ftrace: Use STK_GOT in ftrace_mprofile.S
  powerpc/ftrace: Regroup PPC64 specific operations in ftrace_mprofile.S
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/bpf: Simplify bpf_to_ppc() and adopt it for powerpc64</title>
<updated>2022-03-07T13:04:59+00:00</updated>
<author>
<name>Naveen N. Rao</name>
<email>naveen.n.rao@linux.vnet.ibm.com</email>
</author>
<published>2022-02-14T10:41:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=49c3af43e65fbcc13860e0cf5fb2507b13e9724c'/>
<id>49c3af43e65fbcc13860e0cf5fb2507b13e9724c</id>
<content type='text'>
Convert bpf_to_ppc() to a macro to help simplify its usage since
codegen_context is available in all places it is used. Adopt it also for
powerpc64 for uniformity and get rid of the global b2p structure.

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/09f0540ce3e0cd4120b5b33993b5e73b6ef9e979.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Convert bpf_to_ppc() to a macro to help simplify its usage since
codegen_context is available in all places it is used. Adopt it also for
powerpc64 for uniformity and get rid of the global b2p structure.

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/09f0540ce3e0cd4120b5b33993b5e73b6ef9e979.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc64/bpf: Store temp registers' bpf to ppc mapping</title>
<updated>2022-03-07T13:04:59+00:00</updated>
<author>
<name>Jordan Niethe</name>
<email>jniethe5@gmail.com</email>
</author>
<published>2022-02-14T10:41:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3a3fc9bf103974d9a886fa37087d5d491c806e00'/>
<id>3a3fc9bf103974d9a886fa37087d5d491c806e00</id>
<content type='text'>
In bpf_jit_build_body(), the mapping of TMP_REG_1 and TMP_REG_2's bpf
register to ppc register is evalulated at every use despite not
changing. Instead, determine the ppc register once and store the result.

Signed-off-by: Jordan Niethe &lt;jniethe5@gmail.com&gt;
[Rebased, converted additional usage sites]
Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/0944e2f0fa6dd254ea401f1c946fb6c9a5294278.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In bpf_jit_build_body(), the mapping of TMP_REG_1 and TMP_REG_2's bpf
register to ppc register is evalulated at every use despite not
changing. Instead, determine the ppc register once and store the result.

Signed-off-by: Jordan Niethe &lt;jniethe5@gmail.com&gt;
[Rebased, converted additional usage sites]
Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/0944e2f0fa6dd254ea401f1c946fb6c9a5294278.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/bpf: Use _Rn macros for GPRs</title>
<updated>2022-03-07T13:04:59+00:00</updated>
<author>
<name>Naveen N. Rao</name>
<email>naveen.n.rao@linux.vnet.ibm.com</email>
</author>
<published>2022-02-14T10:41:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=036d559c0bdea75bf4840ba6780790d08572480c'/>
<id>036d559c0bdea75bf4840ba6780790d08572480c</id>
<content type='text'>
Use _Rn macros to specify register names to make their usage clear.

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/7df626b8cdc6141d4295ac16137c82ad570b6637.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use _Rn macros to specify register names to make their usage clear.

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/7df626b8cdc6141d4295ac16137c82ad570b6637.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/bpf: Move bpf_jit64.h into bpf_jit_comp64.c</title>
<updated>2022-03-07T13:04:59+00:00</updated>
<author>
<name>Naveen N. Rao</name>
<email>naveen.n.rao@linux.vnet.ibm.com</email>
</author>
<published>2022-02-14T10:41:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=576a6c3a00c1a2a3645e039b126b52f6c7755e54'/>
<id>576a6c3a00c1a2a3645e039b126b52f6c7755e54</id>
<content type='text'>
There is no need for a separate header anymore. Move the contents of
bpf_jit64.h into bpf_jit_comp64.c

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/b873a8e6eff7d91bf2a2cabdd53082aadfe20761.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There is no need for a separate header anymore. Move the contents of
bpf_jit64.h into bpf_jit_comp64.c

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/b873a8e6eff7d91bf2a2cabdd53082aadfe20761.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/bpf: Cleanup bpf_jit.h</title>
<updated>2022-03-07T13:04:59+00:00</updated>
<author>
<name>Naveen N. Rao</name>
<email>naveen.n.rao@linux.vnet.ibm.com</email>
</author>
<published>2022-02-14T10:41:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7b187dcdb5d348aa916dcda769313512c08e85a5'/>
<id>7b187dcdb5d348aa916dcda769313512c08e85a5</id>
<content type='text'>
- PPC_EX32() is only used by ppc32 JIT. Move it to bpf_jit_comp32.c
- PPC_LI64() is only valid in ppc64. #ifdef it
- PPC_FUNC_ADDR() is not used anymore. Remove it.

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/58f5b66b2f8546bbbee620f62103a8e97a63eb7c.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
- PPC_EX32() is only used by ppc32 JIT. Move it to bpf_jit_comp32.c
- PPC_LI64() is only valid in ppc64. #ifdef it
- PPC_FUNC_ADDR() is not used anymore. Remove it.

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/58f5b66b2f8546bbbee620f62103a8e97a63eb7c.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc64/bpf: Get rid of PPC_BPF_[LL|STL|STLU] macros</title>
<updated>2022-03-07T13:04:58+00:00</updated>
<author>
<name>Naveen N. Rao</name>
<email>naveen.n.rao@linux.vnet.ibm.com</email>
</author>
<published>2022-02-14T10:41:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=794abc08d75e9f2833f493090af14b748e182c5f'/>
<id>794abc08d75e9f2833f493090af14b748e182c5f</id>
<content type='text'>
All these macros now have a single user. Expand their usage in place.

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/e0526fc7633a34f983a7a330712b55bdfaf20482.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
All these macros now have a single user. Expand their usage in place.

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/e0526fc7633a34f983a7a330712b55bdfaf20482.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc64/bpf: Convert some of the uses of PPC_BPF_[LL|STL] to PPC_BPF_[LD|STD]</title>
<updated>2022-03-07T13:04:58+00:00</updated>
<author>
<name>Naveen N. Rao</name>
<email>naveen.n.rao@linux.vnet.ibm.com</email>
</author>
<published>2022-02-14T10:41:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=391c271f4deb7356482d12f962a6fc018b6a3fb0'/>
<id>391c271f4deb7356482d12f962a6fc018b6a3fb0</id>
<content type='text'>
PPC_BPF_[LL|STL] are macros meant for scenarios where we may have to
deal with a non-word aligned offset. Limit their usage to only those
scenarios by converting the rest to just use PPC_BPF_[LD|STD].

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/0eb472428165a307f6fdaf22b0c33cbf13a9a635.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
PPC_BPF_[LL|STL] are macros meant for scenarios where we may have to
deal with a non-word aligned offset. Limit their usage to only those
scenarios by converting the rest to just use PPC_BPF_[LD|STD].

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/0eb472428165a307f6fdaf22b0c33cbf13a9a635.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/bpf: Rename PPC_BL_ABS() to PPC_BL()</title>
<updated>2022-03-07T13:04:58+00:00</updated>
<author>
<name>Naveen N. Rao</name>
<email>naveen.n.rao@linux.vnet.ibm.com</email>
</author>
<published>2022-02-14T10:41:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=74bbe3f08463c48a27088be4823a5803b7f7d9a1'/>
<id>74bbe3f08463c48a27088be4823a5803b7f7d9a1</id>
<content type='text'>
PPC_BL_ABS() is just doing a relative branch with link. The name
suggests that it is for branching to an absolute address, which is
incorrect. Rename the macro to a more appropriate PPC_BL().

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/f0e57b6c7a6ee40dba645535b70da46f46e8af5e.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
PPC_BL_ABS() is just doing a relative branch with link. The name
suggests that it is for branching to an absolute address, which is
incorrect. Rename the macro to a more appropriate PPC_BL().

Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/f0e57b6c7a6ee40dba645535b70da46f46e8af5e.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc64/bpf: Optimize instruction sequence used for function calls</title>
<updated>2022-03-07T13:04:58+00:00</updated>
<author>
<name>Naveen N. Rao</name>
<email>naveen.n.rao@linux.vnet.ibm.com</email>
</author>
<published>2022-02-14T10:41:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=feb6307289d85262c5aed04d6f192d38abba7c45'/>
<id>feb6307289d85262c5aed04d6f192d38abba7c45</id>
<content type='text'>
When calling BPF helpers, we load the function address to call into a
register. This can result in upto 5 instructions. Optimize this by
instead using the kernel toc in r2 and adjusting offset to the BPF
helper. This works since all BPF helpers are part of kernel text, and
all BPF programs/functions utilize the kernel TOC.

Further more:
- load the actual function entry address in elf v1, rather than loading
  it through the function descriptor address.
- load the Local Entry Point (LEP) in elf v2 skipping TOC setup.
- consolidate code across elf abi v1 and v2 by using r12 on both.

Reported-by: Anton Blanchard &lt;anton@ozlabs.org&gt;
Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/1233c7544e60dcb021c52b1f840b0f21a87b33ed.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When calling BPF helpers, we load the function address to call into a
register. This can result in upto 5 instructions. Optimize this by
instead using the kernel toc in r2 and adjusting offset to the BPF
helper. This works since all BPF helpers are part of kernel text, and
all BPF programs/functions utilize the kernel TOC.

Further more:
- load the actual function entry address in elf v1, rather than loading
  it through the function descriptor address.
- load the Local Entry Point (LEP) in elf v2 skipping TOC setup.
- consolidate code across elf abi v1 and v2 by using r12 on both.

Reported-by: Anton Blanchard &lt;anton@ozlabs.org&gt;
Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/1233c7544e60dcb021c52b1f840b0f21a87b33ed.1644834730.git.naveen.n.rao@linux.vnet.ibm.com

</pre>
</div>
</content>
</entry>
</feed>
