<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/powerpc, branch linux-6.3.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>powerpc/mm/dax: Fix the condition when checking if altmap vmemap can cross-boundary</title>
<updated>2023-07-11T17:39:48+00:00</updated>
<author>
<name>Aneesh Kumar K.V</name>
<email>aneesh.kumar@linux.ibm.com</email>
</author>
<published>2023-06-16T11:08:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bf945eb7a338843cc87f6c89a9c54986382f3669'/>
<id>bf945eb7a338843cc87f6c89a9c54986382f3669</id>
<content type='text'>
[ Upstream commit c8eebc4a99f15280654f23e914e746c40a516e50 ]

Without this fix, the last subsection vmemmap can end up in memory even if
the namespace is created with -M mem and has sufficient space in the altmap
area.

Fixes: cf387d9644d8 ("libnvdimm/altmap: Track namespace boundaries in altmap")
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.ibm.com&gt;
Tested-by: Sachin Sant &lt;sachinp@linux.ibm.com &lt;mailto:sachinp@linux.ibm.com&gt;&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20230616110826.344417-6-aneesh.kumar@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c8eebc4a99f15280654f23e914e746c40a516e50 ]

Without this fix, the last subsection vmemmap can end up in memory even if
the namespace is created with -M mem and has sufficient space in the altmap
area.

Fixes: cf387d9644d8 ("libnvdimm/altmap: Track namespace boundaries in altmap")
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.ibm.com&gt;
Tested-by: Sachin Sant &lt;sachinp@linux.ibm.com &lt;mailto:sachinp@linux.ibm.com&gt;&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20230616110826.344417-6-aneesh.kumar@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/book3s64/mm: Fix DirectMap stats in /proc/meminfo</title>
<updated>2023-07-11T17:39:48+00:00</updated>
<author>
<name>Aneesh Kumar K.V</name>
<email>aneesh.kumar@linux.ibm.com</email>
</author>
<published>2023-06-16T11:08:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a07449723fbca25d958ea022dd55ffc46f3bb410'/>
<id>a07449723fbca25d958ea022dd55ffc46f3bb410</id>
<content type='text'>
[ Upstream commit 0da90af431abc3f497a38ec9ef6e43b0d0dabe80 ]

On memory unplug reduce DirectMap page count correctly.
root@ubuntu-guest:# grep Direct /proc/meminfo
DirectMap4k:           0 kB
DirectMap64k:           0 kB
DirectMap2M:    115343360 kB
DirectMap1G:           0 kB

Before fix:
root@ubuntu-guest:# ndctl disable-namespace all
disabled 1 namespace
root@ubuntu-guest:# grep Direct /proc/meminfo
DirectMap4k:           0 kB
DirectMap64k:           0 kB
DirectMap2M:    115343360 kB
DirectMap1G:           0 kB

After fix:
root@ubuntu-guest:# ndctl disable-namespace all
disabled 1 namespace
root@ubuntu-guest:# grep Direct /proc/meminfo
DirectMap4k:           0 kB
DirectMap64k:           0 kB
DirectMap2M:    104857600 kB
DirectMap1G:           0 kB

Fixes: a2dc009afa9a ("powerpc/mm/book3s/radix: Add mapping statistics")
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.ibm.com&gt;
Tested-by: Sachin Sant &lt;sachinp@linux.ibm.com &lt;mailto:sachinp@linux.ibm.com&gt;&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20230616110826.344417-4-aneesh.kumar@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 0da90af431abc3f497a38ec9ef6e43b0d0dabe80 ]

On memory unplug reduce DirectMap page count correctly.
root@ubuntu-guest:# grep Direct /proc/meminfo
DirectMap4k:           0 kB
DirectMap64k:           0 kB
DirectMap2M:    115343360 kB
DirectMap1G:           0 kB

Before fix:
root@ubuntu-guest:# ndctl disable-namespace all
disabled 1 namespace
root@ubuntu-guest:# grep Direct /proc/meminfo
DirectMap4k:           0 kB
DirectMap64k:           0 kB
DirectMap2M:    115343360 kB
DirectMap1G:           0 kB

After fix:
root@ubuntu-guest:# ndctl disable-namespace all
disabled 1 namespace
root@ubuntu-guest:# grep Direct /proc/meminfo
DirectMap4k:           0 kB
DirectMap64k:           0 kB
DirectMap2M:    104857600 kB
DirectMap1G:           0 kB

Fixes: a2dc009afa9a ("powerpc/mm/book3s/radix: Add mapping statistics")
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.ibm.com&gt;
Tested-by: Sachin Sant &lt;sachinp@linux.ibm.com &lt;mailto:sachinp@linux.ibm.com&gt;&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20230616110826.344417-4-aneesh.kumar@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc: update ppc_save_regs to save current r1 in pt_regs</title>
<updated>2023-07-11T17:39:48+00:00</updated>
<author>
<name>Aditya Gupta</name>
<email>adityag@linux.ibm.com</email>
</author>
<published>2023-06-15T09:10:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ca9465056e1a40ec0b729c115871b1b17755b631'/>
<id>ca9465056e1a40ec0b729c115871b1b17755b631</id>
<content type='text'>
[ Upstream commit b684c09f09e7a6af3794d4233ef785819e72db79 ]

ppc_save_regs() skips one stack frame while saving the CPU register states.
Instead of saving current R1, it pulls the previous stack frame pointer.

When vmcores caused by direct panic call (such as `echo c &gt;
/proc/sysrq-trigger`), are debugged with gdb, gdb fails to show the
backtrace correctly. On further analysis, it was found that it was because
of mismatch between r1 and NIP.

GDB uses NIP to get current function symbol and uses corresponding debug
info of that function to unwind previous frames, but due to the
mismatching r1 and NIP, the unwinding does not work, and it fails to
unwind to the 2nd frame and hence does not show the backtrace.

GDB backtrace with vmcore of kernel without this patch:

---------
(gdb) bt
 #0  0xc0000000002a53e8 in crash_setup_regs (oldregs=&lt;optimized out&gt;,
    newregs=0xc000000004f8f8d8) at ./arch/powerpc/include/asm/kexec.h:69
 #1  __crash_kexec (regs=&lt;optimized out&gt;) at kernel/kexec_core.c:974
 #2  0x0000000000000063 in ?? ()
 #3  0xc000000003579320 in ?? ()
---------

Further analysis revealed that the mismatch occurred because
"ppc_save_regs" was saving the previous stack's SP instead of the current
r1. This patch fixes this by storing current r1 in the saved pt_regs.

GDB backtrace with vmcore of patched kernel:

--------
(gdb) bt
 #0  0xc0000000002a53e8 in crash_setup_regs (oldregs=0x0, newregs=0xc00000000670b8d8)
    at ./arch/powerpc/include/asm/kexec.h:69
 #1  __crash_kexec (regs=regs@entry=0x0) at kernel/kexec_core.c:974
 #2  0xc000000000168918 in panic (fmt=fmt@entry=0xc000000001654a60 "sysrq triggered crash\n")
    at kernel/panic.c:358
 #3  0xc000000000b735f8 in sysrq_handle_crash (key=&lt;optimized out&gt;) at drivers/tty/sysrq.c:155
 #4  0xc000000000b742cc in __handle_sysrq (key=key@entry=99, check_mask=check_mask@entry=false)
    at drivers/tty/sysrq.c:602
 #5  0xc000000000b7506c in write_sysrq_trigger (file=&lt;optimized out&gt;, buf=&lt;optimized out&gt;,
    count=2, ppos=&lt;optimized out&gt;) at drivers/tty/sysrq.c:1163
 #6  0xc00000000069a7bc in pde_write (ppos=&lt;optimized out&gt;, count=&lt;optimized out&gt;,
    buf=&lt;optimized out&gt;, file=&lt;optimized out&gt;, pde=0xc00000000362cb40) at fs/proc/inode.c:340
 #7  proc_reg_write (file=&lt;optimized out&gt;, buf=&lt;optimized out&gt;, count=&lt;optimized out&gt;,
    ppos=&lt;optimized out&gt;) at fs/proc/inode.c:352
 #8  0xc0000000005b3bbc in vfs_write (file=file@entry=0xc000000006aa6b00,
    buf=buf@entry=0x61f498b4f60 &lt;error: Cannot access memory at address 0x61f498b4f60&gt;,
    count=count@entry=2, pos=pos@entry=0xc00000000670bda0) at fs/read_write.c:582
 #9  0xc0000000005b4264 in ksys_write (fd=&lt;optimized out&gt;,
    buf=0x61f498b4f60 &lt;error: Cannot access memory at address 0x61f498b4f60&gt;, count=2)
    at fs/read_write.c:637
 #10 0xc00000000002ea2c in system_call_exception (regs=0xc00000000670be80, r0=&lt;optimized out&gt;)
    at arch/powerpc/kernel/syscall.c:171
 #11 0xc00000000000c270 in system_call_vectored_common ()
    at arch/powerpc/kernel/interrupt_64.S:192
--------

Nick adds:
  So this now saves regs as though it was an interrupt taken in the
  caller, at the instruction after the call to ppc_save_regs, whereas
  previously the NIP was there, but R1 came from the caller's caller and
  that mismatch is what causes gdb's dwarf unwinder to go haywire.

Signed-off-by: Aditya Gupta &lt;adityag@linux.ibm.com&gt;
Fixes: d16a58f8854b1 ("powerpc: Improve ppc_save_regs()")
Reivewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20230615091047.90433-1-adityag@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b684c09f09e7a6af3794d4233ef785819e72db79 ]

ppc_save_regs() skips one stack frame while saving the CPU register states.
Instead of saving current R1, it pulls the previous stack frame pointer.

When vmcores caused by direct panic call (such as `echo c &gt;
/proc/sysrq-trigger`), are debugged with gdb, gdb fails to show the
backtrace correctly. On further analysis, it was found that it was because
of mismatch between r1 and NIP.

GDB uses NIP to get current function symbol and uses corresponding debug
info of that function to unwind previous frames, but due to the
mismatching r1 and NIP, the unwinding does not work, and it fails to
unwind to the 2nd frame and hence does not show the backtrace.

GDB backtrace with vmcore of kernel without this patch:

---------
(gdb) bt
 #0  0xc0000000002a53e8 in crash_setup_regs (oldregs=&lt;optimized out&gt;,
    newregs=0xc000000004f8f8d8) at ./arch/powerpc/include/asm/kexec.h:69
 #1  __crash_kexec (regs=&lt;optimized out&gt;) at kernel/kexec_core.c:974
 #2  0x0000000000000063 in ?? ()
 #3  0xc000000003579320 in ?? ()
---------

Further analysis revealed that the mismatch occurred because
"ppc_save_regs" was saving the previous stack's SP instead of the current
r1. This patch fixes this by storing current r1 in the saved pt_regs.

GDB backtrace with vmcore of patched kernel:

--------
(gdb) bt
 #0  0xc0000000002a53e8 in crash_setup_regs (oldregs=0x0, newregs=0xc00000000670b8d8)
    at ./arch/powerpc/include/asm/kexec.h:69
 #1  __crash_kexec (regs=regs@entry=0x0) at kernel/kexec_core.c:974
 #2  0xc000000000168918 in panic (fmt=fmt@entry=0xc000000001654a60 "sysrq triggered crash\n")
    at kernel/panic.c:358
 #3  0xc000000000b735f8 in sysrq_handle_crash (key=&lt;optimized out&gt;) at drivers/tty/sysrq.c:155
 #4  0xc000000000b742cc in __handle_sysrq (key=key@entry=99, check_mask=check_mask@entry=false)
    at drivers/tty/sysrq.c:602
 #5  0xc000000000b7506c in write_sysrq_trigger (file=&lt;optimized out&gt;, buf=&lt;optimized out&gt;,
    count=2, ppos=&lt;optimized out&gt;) at drivers/tty/sysrq.c:1163
 #6  0xc00000000069a7bc in pde_write (ppos=&lt;optimized out&gt;, count=&lt;optimized out&gt;,
    buf=&lt;optimized out&gt;, file=&lt;optimized out&gt;, pde=0xc00000000362cb40) at fs/proc/inode.c:340
 #7  proc_reg_write (file=&lt;optimized out&gt;, buf=&lt;optimized out&gt;, count=&lt;optimized out&gt;,
    ppos=&lt;optimized out&gt;) at fs/proc/inode.c:352
 #8  0xc0000000005b3bbc in vfs_write (file=file@entry=0xc000000006aa6b00,
    buf=buf@entry=0x61f498b4f60 &lt;error: Cannot access memory at address 0x61f498b4f60&gt;,
    count=count@entry=2, pos=pos@entry=0xc00000000670bda0) at fs/read_write.c:582
 #9  0xc0000000005b4264 in ksys_write (fd=&lt;optimized out&gt;,
    buf=0x61f498b4f60 &lt;error: Cannot access memory at address 0x61f498b4f60&gt;, count=2)
    at fs/read_write.c:637
 #10 0xc00000000002ea2c in system_call_exception (regs=0xc00000000670be80, r0=&lt;optimized out&gt;)
    at arch/powerpc/kernel/syscall.c:171
 #11 0xc00000000000c270 in system_call_vectored_common ()
    at arch/powerpc/kernel/interrupt_64.S:192
--------

Nick adds:
  So this now saves regs as though it was an interrupt taken in the
  caller, at the instruction after the call to ppc_save_regs, whereas
  previously the NIP was there, but R1 came from the caller's caller and
  that mismatch is what causes gdb's dwarf unwinder to go haywire.

Signed-off-by: Aditya Gupta &lt;adityag@linux.ibm.com&gt;
Fixes: d16a58f8854b1 ("powerpc: Improve ppc_save_regs()")
Reivewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20230615091047.90433-1-adityag@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/powernv/sriov: perform null check on iov before dereferencing iov</title>
<updated>2023-07-11T17:39:48+00:00</updated>
<author>
<name>Colin Ian King</name>
<email>colin.i.king@gmail.com</email>
</author>
<published>2023-06-08T09:58:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6314465b88072a6b6f3b3c12a7898abe09095f95'/>
<id>6314465b88072a6b6f3b3c12a7898abe09095f95</id>
<content type='text'>
[ Upstream commit f4f913c980bc6abe0ccfe88fe3909c125afe4a2d ]

Currently pointer iov is being dereferenced before the null check of iov
which can lead to null pointer dereference errors. Fix this by moving the
iov null check before the dereferencing.

Detected using cppcheck static analysis:
linux/arch/powerpc/platforms/powernv/pci-sriov.c:597:12: warning: Either
the condition '!iov' is redundant or there is possible null pointer
dereference: iov. [nullPointerRedundantCheck]
 num_vfs = iov-&gt;num_vfs;
           ^

Fixes: 052da31d45fc ("powerpc/powernv/sriov: De-indent setup and teardown")
Signed-off-by: Colin Ian King &lt;colin.i.king@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20230608095849.1147969-1-colin.i.king@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f4f913c980bc6abe0ccfe88fe3909c125afe4a2d ]

Currently pointer iov is being dereferenced before the null check of iov
which can lead to null pointer dereference errors. Fix this by moving the
iov null check before the dereferencing.

Detected using cppcheck static analysis:
linux/arch/powerpc/platforms/powernv/pci-sriov.c:597:12: warning: Either
the condition '!iov' is redundant or there is possible null pointer
dereference: iov. [nullPointerRedundantCheck]
 num_vfs = iov-&gt;num_vfs;
           ^

Fixes: 052da31d45fc ("powerpc/powernv/sriov: De-indent setup and teardown")
Signed-off-by: Colin Ian King &lt;colin.i.king@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20230608095849.1147969-1-colin.i.king@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/64s: Fix VAS mm use after free</title>
<updated>2023-07-11T17:39:48+00:00</updated>
<author>
<name>Nicholas Piggin</name>
<email>npiggin@gmail.com</email>
</author>
<published>2023-06-07T10:10:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=db8657fdd53c5e3069149d7f957cb60e63027bb2'/>
<id>db8657fdd53c5e3069149d7f957cb60e63027bb2</id>
<content type='text'>
[ Upstream commit b4bda59b47879cce38a6ec5a01cd3cac702b5331 ]

The refcount on mm is dropped before the coprocessor is detached.

Reported-by: Sachin Sant &lt;sachinp@linux.ibm.com&gt;
Fixes: 7bc6f71bdff5f ("powerpc/vas: Define and use common vas_window struct")
Fixes: b22f2d88e435c ("powerpc/pseries/vas: Integrate API with open/close windows")
Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Tested-by: Sachin Sant &lt;sachinp@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20230607101024.14559-1-npiggin@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b4bda59b47879cce38a6ec5a01cd3cac702b5331 ]

The refcount on mm is dropped before the coprocessor is detached.

Reported-by: Sachin Sant &lt;sachinp@linux.ibm.com&gt;
Fixes: 7bc6f71bdff5f ("powerpc/vas: Define and use common vas_window struct")
Fixes: b22f2d88e435c ("powerpc/pseries/vas: Integrate API with open/close windows")
Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Tested-by: Sachin Sant &lt;sachinp@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20230607101024.14559-1-npiggin@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/signal32: Force inlining of __unsafe_save_user_regs() and save_tm_user_regs_unsafe()</title>
<updated>2023-07-11T17:39:47+00:00</updated>
<author>
<name>Christophe Leroy</name>
<email>christophe.leroy@csgroup.eu</email>
</author>
<published>2023-06-05T08:58:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=885e8df797819b613bb94ee0d91e7742406a291e'/>
<id>885e8df797819b613bb94ee0d91e7742406a291e</id>
<content type='text'>
[ Upstream commit a03b1a0b19398a47489fdcef02ec19c2ba05a15d ]

Looking at generated code for handle_signal32() shows calls to a
function called __unsafe_save_user_regs.constprop.0 while user access
is open.

And that __unsafe_save_user_regs.constprop.0 function has two nops at
the begining, allowing it to be traced, which is unexpected during
user access open window.

The solution could be to mark __unsafe_save_user_regs() no trace, but
to be on the safe side the most efficient is to flag it __always_inline
as already done for function __unsafe_restore_general_regs(). The
function is relatively small and only called twice, so the size
increase will remain in the noise.

Do the same with save_tm_user_regs_unsafe() as it may suffer the
same issue.

Fixes: ef75e7318294 ("powerpc/signal32: Transform save_user_regs() and save_tm_user_regs() in 'unsafe' version")
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/7e469c8f01860a69c1ada3ca6a5e2aa65f0f74b2.1685955220.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit a03b1a0b19398a47489fdcef02ec19c2ba05a15d ]

Looking at generated code for handle_signal32() shows calls to a
function called __unsafe_save_user_regs.constprop.0 while user access
is open.

And that __unsafe_save_user_regs.constprop.0 function has two nops at
the begining, allowing it to be traced, which is unexpected during
user access open window.

The solution could be to mark __unsafe_save_user_regs() no trace, but
to be on the safe side the most efficient is to flag it __always_inline
as already done for function __unsafe_restore_general_regs(). The
function is relatively small and only called twice, so the size
increase will remain in the noise.

Do the same with save_tm_user_regs_unsafe() as it may suffer the
same issue.

Fixes: ef75e7318294 ("powerpc/signal32: Transform save_user_regs() and save_tm_user_regs() in 'unsafe' version")
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/7e469c8f01860a69c1ada3ca6a5e2aa65f0f74b2.1685955220.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/interrupt: Don't read MSR from interrupt_exit_kernel_prepare()</title>
<updated>2023-07-11T17:39:47+00:00</updated>
<author>
<name>Christophe Leroy</name>
<email>christophe.leroy@csgroup.eu</email>
</author>
<published>2023-06-05T08:55:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=243003b0c1618b5580b450dde1353c997b3996cc'/>
<id>243003b0c1618b5580b450dde1353c997b3996cc</id>
<content type='text'>
[ Upstream commit 0eb089a72fda3f7969e6277804bde75dc1474a14 ]

A disassembly of interrupt_exit_kernel_prepare() shows a useless read
of MSR register. This is shown by r9 being re-used immediately without
doing anything with the value read.

  c000e0e0:       60 00 00 00     nop
  c000e0e4:       7d 3a c2 a6     mfmd_ap r9
  c000e0e8:       7d 20 00 a6     mfmsr   r9
  c000e0ec:       7c 51 13 a6     mtspr   81,r2
  c000e0f0:       81 3f 00 84     lwz     r9,132(r31)
  c000e0f4:       71 29 80 00     andi.   r9,r9,32768

This is due to the use of local_irq_save(). The flags read by
local_irq_save() are never used, use local_irq_disable() instead.

Fixes: 13799748b957 ("powerpc/64: use interrupt restart table to speed up return from interrupt")
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Reviewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/df36c6205ab64326fb1b991993c82057e92ace2f.1685955214.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 0eb089a72fda3f7969e6277804bde75dc1474a14 ]

A disassembly of interrupt_exit_kernel_prepare() shows a useless read
of MSR register. This is shown by r9 being re-used immediately without
doing anything with the value read.

  c000e0e0:       60 00 00 00     nop
  c000e0e4:       7d 3a c2 a6     mfmd_ap r9
  c000e0e8:       7d 20 00 a6     mfmsr   r9
  c000e0ec:       7c 51 13 a6     mtspr   81,r2
  c000e0f0:       81 3f 00 84     lwz     r9,132(r31)
  c000e0f4:       71 29 80 00     andi.   r9,r9,32768

This is due to the use of local_irq_save(). The flags read by
local_irq_save() are never used, use local_irq_disable() instead.

Fixes: 13799748b957 ("powerpc/64: use interrupt restart table to speed up return from interrupt")
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Reviewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/df36c6205ab64326fb1b991993c82057e92ace2f.1685955214.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/mm: convert coprocessor fault to lock_mm_and_find_vma()</title>
<updated>2023-07-01T11:14:46+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-06-24T18:17:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=723b929cbc2a032f581e0b603ad040470ed883f8'/>
<id>723b929cbc2a032f581e0b603ad040470ed883f8</id>
<content type='text'>
commit 2cd76c50d0b41cec5c87abfcdf25b236a2793fb6 upstream.

This is one of the simple cases, except there's no pt_regs pointer.
Which is fine, as lock_mm_and_find_vma() is set up to work fine with a
NULL pt_regs.

Powerpc already enabled LOCK_MM_AND_FIND_VMA for the main CPU faulting,
so we can just use the helper without any extra work.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
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<pre>
commit 2cd76c50d0b41cec5c87abfcdf25b236a2793fb6 upstream.

This is one of the simple cases, except there's no pt_regs pointer.
Which is fine, as lock_mm_and_find_vma() is set up to work fine with a
NULL pt_regs.

Powerpc already enabled LOCK_MM_AND_FIND_VMA for the main CPU faulting,
so we can just use the helper without any extra work.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/mm: Convert to using lock_mm_and_find_vma()</title>
<updated>2023-07-01T11:14:45+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2023-06-16T05:51:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=337a7cb4a6c3c3c8a029b758f8b99435ac2c99a1'/>
<id>337a7cb4a6c3c3c8a029b758f8b99435ac2c99a1</id>
<content type='text'>
commit e6fe228c4ffafdfc970cf6d46883a1f481baf7ea upstream.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e6fe228c4ffafdfc970cf6d46883a1f481baf7ea upstream.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/purgatory: remove PGO flags</title>
<updated>2023-06-21T14:02:09+00:00</updated>
<author>
<name>Ricardo Ribalda</name>
<email>ribalda@chromium.org</email>
</author>
<published>2023-05-19T14:47:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4f96a4a4943265b4bf7ad702eaef67d9aafd8790'/>
<id>4f96a4a4943265b4bf7ad702eaef67d9aafd8790</id>
<content type='text'>
commit 20188baceb7a1463dc0bcb0c8678b69c2f447df6 upstream.

If profile-guided optimization is enabled, the purgatory ends up with
multiple .text sections.  This is not supported by kexec and crashes the
system.

Link: https://lkml.kernel.org/r/20230321-kexec_clang16-v7-3-b05c520b7296@chromium.org
Fixes: 930457057abe ("kernel/kexec_file.c: split up __kexec_load_puragory")
Signed-off-by: Ricardo Ribalda &lt;ribalda@chromium.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Dave Young &lt;dyoung@redhat.com&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Philipp Rudo &lt;prudo@redhat.com&gt;
Cc: Ross Zwisler &lt;zwisler@google.com&gt;
Cc: Simon Horman &lt;horms@kernel.org&gt;
Cc: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Tom Rix &lt;trix@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 20188baceb7a1463dc0bcb0c8678b69c2f447df6 upstream.

If profile-guided optimization is enabled, the purgatory ends up with
multiple .text sections.  This is not supported by kexec and crashes the
system.

Link: https://lkml.kernel.org/r/20230321-kexec_clang16-v7-3-b05c520b7296@chromium.org
Fixes: 930457057abe ("kernel/kexec_file.c: split up __kexec_load_puragory")
Signed-off-by: Ricardo Ribalda &lt;ribalda@chromium.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Dave Young &lt;dyoung@redhat.com&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Philipp Rudo &lt;prudo@redhat.com&gt;
Cc: Ross Zwisler &lt;zwisler@google.com&gt;
Cc: Simon Horman &lt;horms@kernel.org&gt;
Cc: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Tom Rix &lt;trix@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
