<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/powerpc, branch v5.4.232</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>powerpc/imc-pmu: Revert nest_init_lock to being a mutex</title>
<updated>2023-02-22T11:50:29+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2023-01-30T01:44:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8edda487f0855ca2b0ba4dc15b41a3b4d7ed80c2'/>
<id>8edda487f0855ca2b0ba4dc15b41a3b4d7ed80c2</id>
<content type='text'>
commit ad53db4acb415976761d7302f5b02e97f2bd097e upstream.

The recent commit 76d588dddc45 ("powerpc/imc-pmu: Fix use of mutex in
IRQs disabled section") fixed warnings (and possible deadlocks) in the
IMC PMU driver by converting the locking to use spinlocks.

It also converted the init-time nest_init_lock to a spinlock, even
though it's not used at runtime in IRQ disabled sections or while
holding other spinlocks.

This leads to warnings such as:

  BUG: sleeping function called from invalid context at include/linux/percpu-rwsem.h:49
  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0
  preempt_count: 1, expected: 0
  CPU: 7 PID: 1 Comm: swapper/0 Not tainted 6.2.0-rc2-14719-gf12cd06109f4-dirty #1
  Hardware name: Mambo,Simulated-System POWER9 0x4e1203 opal:v6.6.6 PowerNV
  Call Trace:
    dump_stack_lvl+0x74/0xa8 (unreliable)
    __might_resched+0x178/0x1a0
    __cpuhp_setup_state+0x64/0x1e0
    init_imc_pmu+0xe48/0x1250
    opal_imc_counters_probe+0x30c/0x6a0
    platform_probe+0x78/0x110
    really_probe+0x104/0x420
    __driver_probe_device+0xb0/0x170
    driver_probe_device+0x58/0x180
    __driver_attach+0xd8/0x250
    bus_for_each_dev+0xb4/0x140
    driver_attach+0x34/0x50
    bus_add_driver+0x1e8/0x2d0
    driver_register+0xb4/0x1c0
    __platform_driver_register+0x38/0x50
    opal_imc_driver_init+0x2c/0x40
    do_one_initcall+0x80/0x360
    kernel_init_freeable+0x310/0x3b8
    kernel_init+0x30/0x1a0
    ret_from_kernel_thread+0x5c/0x64

Fix it by converting nest_init_lock back to a mutex, so that we can call
sleeping functions while holding it. There is no interaction between
nest_init_lock and the runtime spinlocks used by the actual PMU routines.

Fixes: 76d588dddc45 ("powerpc/imc-pmu: Fix use of mutex in IRQs disabled section")
Tested-by: Kajol Jain&lt;kjain@linux.ibm.com&gt;
Reviewed-by: Kajol Jain&lt;kjain@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20230130014401.540543-1-mpe@ellerman.id.au
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 ad53db4acb415976761d7302f5b02e97f2bd097e upstream.

The recent commit 76d588dddc45 ("powerpc/imc-pmu: Fix use of mutex in
IRQs disabled section") fixed warnings (and possible deadlocks) in the
IMC PMU driver by converting the locking to use spinlocks.

It also converted the init-time nest_init_lock to a spinlock, even
though it's not used at runtime in IRQ disabled sections or while
holding other spinlocks.

This leads to warnings such as:

  BUG: sleeping function called from invalid context at include/linux/percpu-rwsem.h:49
  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0
  preempt_count: 1, expected: 0
  CPU: 7 PID: 1 Comm: swapper/0 Not tainted 6.2.0-rc2-14719-gf12cd06109f4-dirty #1
  Hardware name: Mambo,Simulated-System POWER9 0x4e1203 opal:v6.6.6 PowerNV
  Call Trace:
    dump_stack_lvl+0x74/0xa8 (unreliable)
    __might_resched+0x178/0x1a0
    __cpuhp_setup_state+0x64/0x1e0
    init_imc_pmu+0xe48/0x1250
    opal_imc_counters_probe+0x30c/0x6a0
    platform_probe+0x78/0x110
    really_probe+0x104/0x420
    __driver_probe_device+0xb0/0x170
    driver_probe_device+0x58/0x180
    __driver_attach+0xd8/0x250
    bus_for_each_dev+0xb4/0x140
    driver_attach+0x34/0x50
    bus_add_driver+0x1e8/0x2d0
    driver_register+0xb4/0x1c0
    __platform_driver_register+0x38/0x50
    opal_imc_driver_init+0x2c/0x40
    do_one_initcall+0x80/0x360
    kernel_init_freeable+0x310/0x3b8
    kernel_init+0x30/0x1a0
    ret_from_kernel_thread+0x5c/0x64

Fix it by converting nest_init_lock back to a mutex, so that we can call
sleeping functions while holding it. There is no interaction between
nest_init_lock and the runtime spinlocks used by the actual PMU routines.

Fixes: 76d588dddc45 ("powerpc/imc-pmu: Fix use of mutex in IRQs disabled section")
Tested-by: Kajol Jain&lt;kjain@linux.ibm.com&gt;
Reviewed-by: Kajol Jain&lt;kjain@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20230130014401.540543-1-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>exit: Add and use make_task_dead.</title>
<updated>2023-02-06T06:52:49+00:00</updated>
<author>
<name>Eric W. Biederman</name>
<email>ebiederm@xmission.com</email>
</author>
<published>2023-02-02T04:42:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9a18c9c8336fff473a2b72707bd14a52298417b8'/>
<id>9a18c9c8336fff473a2b72707bd14a52298417b8</id>
<content type='text'>
commit 0e25498f8cd43c1b5aa327f373dd094e9a006da7 upstream.

There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 0e25498f8cd43c1b5aa327f373dd094e9a006da7 upstream.

There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/imc-pmu: Fix use of mutex in IRQs disabled section</title>
<updated>2023-01-18T10:42:03+00:00</updated>
<author>
<name>Kajol Jain</name>
<email>kjain@linux.ibm.com</email>
</author>
<published>2023-01-06T06:51:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d0c6d2a31026102d4738b47a610bed4401b9834f'/>
<id>d0c6d2a31026102d4738b47a610bed4401b9834f</id>
<content type='text'>
commit 76d588dddc459fefa1da96e0a081a397c5c8e216 upstream.

Current imc-pmu code triggers a WARNING with CONFIG_DEBUG_ATOMIC_SLEEP
and CONFIG_PROVE_LOCKING enabled, while running a thread_imc event.

Command to trigger the warning:
  # perf stat -e thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ sleep 5

   Performance counter stats for 'sleep 5':

                   0      thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/

         5.002117947 seconds time elapsed

         0.000131000 seconds user
         0.001063000 seconds sys

Below is snippet of the warning in dmesg:

  BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
  in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 2869, name: perf-exec
  preempt_count: 2, expected: 0
  4 locks held by perf-exec/2869:
   #0: c00000004325c540 (&amp;sig-&gt;cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0x64/0xa90
   #1: c00000004325c5d8 (&amp;sig-&gt;exec_update_lock){++++}-{3:3}, at: begin_new_exec+0x460/0xef0
   #2: c0000003fa99d4e0 (&amp;cpuctx_lock){-...}-{2:2}, at: perf_event_exec+0x290/0x510
   #3: c000000017ab8418 (&amp;ctx-&gt;lock){....}-{2:2}, at: perf_event_exec+0x29c/0x510
  irq event stamp: 4806
  hardirqs last  enabled at (4805): [&lt;c000000000f65b94&gt;] _raw_spin_unlock_irqrestore+0x94/0xd0
  hardirqs last disabled at (4806): [&lt;c0000000003fae44&gt;] perf_event_exec+0x394/0x510
  softirqs last  enabled at (0): [&lt;c00000000013c404&gt;] copy_process+0xc34/0x1ff0
  softirqs last disabled at (0): [&lt;0000000000000000&gt;] 0x0
  CPU: 36 PID: 2869 Comm: perf-exec Not tainted 6.2.0-rc2-00011-g1247637727f2 #61
  Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
  Call Trace:
    dump_stack_lvl+0x98/0xe0 (unreliable)
    __might_resched+0x2f8/0x310
    __mutex_lock+0x6c/0x13f0
    thread_imc_event_add+0xf4/0x1b0
    event_sched_in+0xe0/0x210
    merge_sched_in+0x1f0/0x600
    visit_groups_merge.isra.92.constprop.166+0x2bc/0x6c0
    ctx_flexible_sched_in+0xcc/0x140
    ctx_sched_in+0x20c/0x2a0
    ctx_resched+0x104/0x1c0
    perf_event_exec+0x340/0x510
    begin_new_exec+0x730/0xef0
    load_elf_binary+0x3f8/0x1e10
  ...
  do not call blocking ops when !TASK_RUNNING; state=2001 set at [&lt;00000000fd63e7cf&gt;] do_nanosleep+0x60/0x1a0
  WARNING: CPU: 36 PID: 2869 at kernel/sched/core.c:9912 __might_sleep+0x9c/0xb0
  CPU: 36 PID: 2869 Comm: sleep Tainted: G        W          6.2.0-rc2-00011-g1247637727f2 #61
  Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
  NIP:  c000000000194a1c LR: c000000000194a18 CTR: c000000000a78670
  REGS: c00000004d2134e0 TRAP: 0700   Tainted: G        W           (6.2.0-rc2-00011-g1247637727f2)
  MSR:  9000000000021033 &lt;SF,HV,ME,IR,DR,RI,LE&gt;  CR: 48002824  XER: 00000000
  CFAR: c00000000013fb64 IRQMASK: 1

The above warning triggered because the current imc-pmu code uses mutex
lock in interrupt disabled sections. The function mutex_lock()
internally calls __might_resched(), which will check if IRQs are
disabled and in case IRQs are disabled, it will trigger the warning.

Fix the issue by changing the mutex lock to spinlock.

Fixes: 8f95faaac56c ("powerpc/powernv: Detect and create IMC device")
Reported-by: Michael Petlan &lt;mpetlan@redhat.com&gt;
Reported-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Signed-off-by: Kajol Jain &lt;kjain@linux.ibm.com&gt;
[mpe: Fix comments, trim oops in change log, add reported-by tags]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20230106065157.182648-1-kjain@linux.ibm.com
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 76d588dddc459fefa1da96e0a081a397c5c8e216 upstream.

Current imc-pmu code triggers a WARNING with CONFIG_DEBUG_ATOMIC_SLEEP
and CONFIG_PROVE_LOCKING enabled, while running a thread_imc event.

Command to trigger the warning:
  # perf stat -e thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ sleep 5

   Performance counter stats for 'sleep 5':

                   0      thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/

         5.002117947 seconds time elapsed

         0.000131000 seconds user
         0.001063000 seconds sys

Below is snippet of the warning in dmesg:

  BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
  in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 2869, name: perf-exec
  preempt_count: 2, expected: 0
  4 locks held by perf-exec/2869:
   #0: c00000004325c540 (&amp;sig-&gt;cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0x64/0xa90
   #1: c00000004325c5d8 (&amp;sig-&gt;exec_update_lock){++++}-{3:3}, at: begin_new_exec+0x460/0xef0
   #2: c0000003fa99d4e0 (&amp;cpuctx_lock){-...}-{2:2}, at: perf_event_exec+0x290/0x510
   #3: c000000017ab8418 (&amp;ctx-&gt;lock){....}-{2:2}, at: perf_event_exec+0x29c/0x510
  irq event stamp: 4806
  hardirqs last  enabled at (4805): [&lt;c000000000f65b94&gt;] _raw_spin_unlock_irqrestore+0x94/0xd0
  hardirqs last disabled at (4806): [&lt;c0000000003fae44&gt;] perf_event_exec+0x394/0x510
  softirqs last  enabled at (0): [&lt;c00000000013c404&gt;] copy_process+0xc34/0x1ff0
  softirqs last disabled at (0): [&lt;0000000000000000&gt;] 0x0
  CPU: 36 PID: 2869 Comm: perf-exec Not tainted 6.2.0-rc2-00011-g1247637727f2 #61
  Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
  Call Trace:
    dump_stack_lvl+0x98/0xe0 (unreliable)
    __might_resched+0x2f8/0x310
    __mutex_lock+0x6c/0x13f0
    thread_imc_event_add+0xf4/0x1b0
    event_sched_in+0xe0/0x210
    merge_sched_in+0x1f0/0x600
    visit_groups_merge.isra.92.constprop.166+0x2bc/0x6c0
    ctx_flexible_sched_in+0xcc/0x140
    ctx_sched_in+0x20c/0x2a0
    ctx_resched+0x104/0x1c0
    perf_event_exec+0x340/0x510
    begin_new_exec+0x730/0xef0
    load_elf_binary+0x3f8/0x1e10
  ...
  do not call blocking ops when !TASK_RUNNING; state=2001 set at [&lt;00000000fd63e7cf&gt;] do_nanosleep+0x60/0x1a0
  WARNING: CPU: 36 PID: 2869 at kernel/sched/core.c:9912 __might_sleep+0x9c/0xb0
  CPU: 36 PID: 2869 Comm: sleep Tainted: G        W          6.2.0-rc2-00011-g1247637727f2 #61
  Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
  NIP:  c000000000194a1c LR: c000000000194a18 CTR: c000000000a78670
  REGS: c00000004d2134e0 TRAP: 0700   Tainted: G        W           (6.2.0-rc2-00011-g1247637727f2)
  MSR:  9000000000021033 &lt;SF,HV,ME,IR,DR,RI,LE&gt;  CR: 48002824  XER: 00000000
  CFAR: c00000000013fb64 IRQMASK: 1

The above warning triggered because the current imc-pmu code uses mutex
lock in interrupt disabled sections. The function mutex_lock()
internally calls __might_resched(), which will check if IRQs are
disabled and in case IRQs are disabled, it will trigger the warning.

Fix the issue by changing the mutex lock to spinlock.

Fixes: 8f95faaac56c ("powerpc/powernv: Detect and create IMC device")
Reported-by: Michael Petlan &lt;mpetlan@redhat.com&gt;
Reported-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Signed-off-by: Kajol Jain &lt;kjain@linux.ibm.com&gt;
[mpe: Fix comments, trim oops in change log, add reported-by tags]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20230106065157.182648-1-kjain@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/rtas: avoid scheduling in rtas_os_term()</title>
<updated>2023-01-18T10:41:43+00:00</updated>
<author>
<name>Nathan Lynch</name>
<email>nathanl@linux.ibm.com</email>
</author>
<published>2022-11-18T15:07:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=515959eb49e6d218a46979d66f36fdef329ac7d2'/>
<id>515959eb49e6d218a46979d66f36fdef329ac7d2</id>
<content type='text'>
[ Upstream commit 6c606e57eecc37d6b36d732b1ff7e55b7dc32dd4 ]

It's unsafe to use rtas_busy_delay() to handle a busy status from
the ibm,os-term RTAS function in rtas_os_term():

Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
BUG: sleeping function called from invalid context at arch/powerpc/kernel/rtas.c:618
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0
preempt_count: 2, expected: 0
CPU: 7 PID: 1 Comm: swapper/0 Tainted: G      D            6.0.0-rc5-02182-gf8553a572277-dirty #9
Call Trace:
[c000000007b8f000] [c000000001337110] dump_stack_lvl+0xb4/0x110 (unreliable)
[c000000007b8f040] [c0000000002440e4] __might_resched+0x394/0x3c0
[c000000007b8f0e0] [c00000000004f680] rtas_busy_delay+0x120/0x1b0
[c000000007b8f100] [c000000000052d04] rtas_os_term+0xb8/0xf4
[c000000007b8f180] [c0000000001150fc] pseries_panic+0x50/0x68
[c000000007b8f1f0] [c000000000036354] ppc_panic_platform_handler+0x34/0x50
[c000000007b8f210] [c0000000002303c4] notifier_call_chain+0xd4/0x1c0
[c000000007b8f2b0] [c0000000002306cc] atomic_notifier_call_chain+0xac/0x1c0
[c000000007b8f2f0] [c0000000001d62b8] panic+0x228/0x4d0
[c000000007b8f390] [c0000000001e573c] do_exit+0x140c/0x1420
[c000000007b8f480] [c0000000001e586c] make_task_dead+0xdc/0x200

Use rtas_busy_delay_time() instead, which signals without side effects
whether to attempt the ibm,os-term RTAS call again.

Signed-off-by: Nathan Lynch &lt;nathanl@linux.ibm.com&gt;
Reviewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Reviewed-by: Andrew Donnellan &lt;ajd@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221118150751.469393-5-nathanl@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 6c606e57eecc37d6b36d732b1ff7e55b7dc32dd4 ]

It's unsafe to use rtas_busy_delay() to handle a busy status from
the ibm,os-term RTAS function in rtas_os_term():

Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
BUG: sleeping function called from invalid context at arch/powerpc/kernel/rtas.c:618
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0
preempt_count: 2, expected: 0
CPU: 7 PID: 1 Comm: swapper/0 Tainted: G      D            6.0.0-rc5-02182-gf8553a572277-dirty #9
Call Trace:
[c000000007b8f000] [c000000001337110] dump_stack_lvl+0xb4/0x110 (unreliable)
[c000000007b8f040] [c0000000002440e4] __might_resched+0x394/0x3c0
[c000000007b8f0e0] [c00000000004f680] rtas_busy_delay+0x120/0x1b0
[c000000007b8f100] [c000000000052d04] rtas_os_term+0xb8/0xf4
[c000000007b8f180] [c0000000001150fc] pseries_panic+0x50/0x68
[c000000007b8f1f0] [c000000000036354] ppc_panic_platform_handler+0x34/0x50
[c000000007b8f210] [c0000000002303c4] notifier_call_chain+0xd4/0x1c0
[c000000007b8f2b0] [c0000000002306cc] atomic_notifier_call_chain+0xac/0x1c0
[c000000007b8f2f0] [c0000000001d62b8] panic+0x228/0x4d0
[c000000007b8f390] [c0000000001e573c] do_exit+0x140c/0x1420
[c000000007b8f480] [c0000000001e586c] make_task_dead+0xdc/0x200

Use rtas_busy_delay_time() instead, which signals without side effects
whether to attempt the ibm,os-term RTAS call again.

Signed-off-by: Nathan Lynch &lt;nathanl@linux.ibm.com&gt;
Reviewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Reviewed-by: Andrew Donnellan &lt;ajd@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221118150751.469393-5-nathanl@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/rtas: avoid device tree lookups in rtas_os_term()</title>
<updated>2023-01-18T10:41:43+00:00</updated>
<author>
<name>Nathan Lynch</name>
<email>nathanl@linux.ibm.com</email>
</author>
<published>2022-11-18T15:07:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c2fa91abf22a705cf02f886cd99cff41f4ceda60'/>
<id>c2fa91abf22a705cf02f886cd99cff41f4ceda60</id>
<content type='text'>
[ Upstream commit ed2213bfb192ab51f09f12e9b49b5d482c6493f3 ]

rtas_os_term() is called during panic. Its behavior depends on a couple
of conditions in the /rtas node of the device tree, the traversal of
which entails locking and local IRQ state changes. If the kernel panics
while devtree_lock is held, rtas_os_term() as currently written could
hang.

Instead of discovering the relevant characteristics at panic time,
cache them in file-static variables at boot. Note the lookup for
"ibm,extended-os-term" is converted to of_property_read_bool() since it
is a boolean property, not an RTAS function token.

Signed-off-by: Nathan Lynch &lt;nathanl@linux.ibm.com&gt;
Reviewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Reviewed-by: Andrew Donnellan &lt;ajd@linux.ibm.com&gt;
[mpe: Incorporate suggested change from Nick]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221118150751.469393-4-nathanl@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 ed2213bfb192ab51f09f12e9b49b5d482c6493f3 ]

rtas_os_term() is called during panic. Its behavior depends on a couple
of conditions in the /rtas node of the device tree, the traversal of
which entails locking and local IRQ state changes. If the kernel panics
while devtree_lock is held, rtas_os_term() as currently written could
hang.

Instead of discovering the relevant characteristics at panic time,
cache them in file-static variables at boot. Note the lookup for
"ibm,extended-os-term" is converted to of_property_read_bool() since it
is a boolean property, not an RTAS function token.

Signed-off-by: Nathan Lynch &lt;nathanl@linux.ibm.com&gt;
Reviewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Reviewed-by: Andrew Donnellan &lt;ajd@linux.ibm.com&gt;
[mpe: Incorporate suggested change from Nick]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221118150751.469393-4-nathanl@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/hv-gpci: Fix hv_gpci event list</title>
<updated>2023-01-18T10:41:30+00:00</updated>
<author>
<name>Kajol Jain</name>
<email>kjain@linux.ibm.com</email>
</author>
<published>2022-11-30T17:45:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=39633b4051eeb1dc7ad01e0d90e156b3ac3a23a4'/>
<id>39633b4051eeb1dc7ad01e0d90e156b3ac3a23a4</id>
<content type='text'>
[ Upstream commit 03f7c1d2a49acd30e38789cd809d3300721e9b0e ]

Based on getPerfCountInfo v1.018 documentation, some of the
hv_gpci events were deprecated for platform firmware that
supports counter_info_version 0x8 or above.

Fix the hv_gpci event list by adding a new attribute group
called "hv_gpci_event_attrs_v6" and a "ENABLE_EVENTS_COUNTERINFO_V6"
macro to enable these events for platform firmware
that supports counter_info_version 0x6 or below. And assigning
the hv_gpci event list based on output counter info version
of underlying plaform.

Fixes: 97bf2640184f ("powerpc/perf/hv-gpci: add the remaining gpci requests")
Signed-off-by: Kajol Jain &lt;kjain@linux.ibm.com&gt;
Reviewed-by: Madhavan Srinivasan &lt;maddy@linux.ibm.com&gt;
Reviewed-by: Athira Rajeev &lt;atrajeev@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221130174513.87501-1-kjain@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 03f7c1d2a49acd30e38789cd809d3300721e9b0e ]

Based on getPerfCountInfo v1.018 documentation, some of the
hv_gpci events were deprecated for platform firmware that
supports counter_info_version 0x8 or above.

Fix the hv_gpci event list by adding a new attribute group
called "hv_gpci_event_attrs_v6" and a "ENABLE_EVENTS_COUNTERINFO_V6"
macro to enable these events for platform firmware
that supports counter_info_version 0x6 or below. And assigning
the hv_gpci event list based on output counter info version
of underlying plaform.

Fixes: 97bf2640184f ("powerpc/perf/hv-gpci: add the remaining gpci requests")
Signed-off-by: Kajol Jain &lt;kjain@linux.ibm.com&gt;
Reviewed-by: Madhavan Srinivasan &lt;maddy@linux.ibm.com&gt;
Reviewed-by: Athira Rajeev &lt;atrajeev@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221130174513.87501-1-kjain@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/83xx/mpc832x_rdb: call platform_device_put() in error case in of_fsl_spi_probe()</title>
<updated>2023-01-18T10:41:30+00:00</updated>
<author>
<name>Yang Yingliang</name>
<email>yangyingliang@huawei.com</email>
</author>
<published>2022-10-29T11:16:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=aed862896d537548a83c82cfaecf6e50820006ca'/>
<id>aed862896d537548a83c82cfaecf6e50820006ca</id>
<content type='text'>
[ Upstream commit 4d0eea415216fe3791da2f65eb41399e70c7bedf ]

If platform_device_add() is not called or failed, it can not call
platform_device_del() to clean up memory, it should call
platform_device_put() in error case.

Fixes: 26f6cb999366 ("[POWERPC] fsl_soc: add support for fsl_spi")
Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221029111626.429971-1-yangyingliang@huawei.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 4d0eea415216fe3791da2f65eb41399e70c7bedf ]

If platform_device_add() is not called or failed, it can not call
platform_device_del() to clean up memory, it should call
platform_device_put() in error case.

Fixes: 26f6cb999366 ("[POWERPC] fsl_soc: add support for fsl_spi")
Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221029111626.429971-1-yangyingliang@huawei.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/perf: callchain validate kernel stack pointer bounds</title>
<updated>2023-01-18T10:41:30+00:00</updated>
<author>
<name>Nicholas Piggin</name>
<email>npiggin@gmail.com</email>
</author>
<published>2022-11-27T12:49:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d539b77bae1e67b8e6192a2ad3dbf12d2b1f0c8f'/>
<id>d539b77bae1e67b8e6192a2ad3dbf12d2b1f0c8f</id>
<content type='text'>
[ Upstream commit 32c5209214bd8d4f8c4e9d9b630ef4c671f58e79 ]

The interrupt frame detection and loads from the hypothetical pt_regs
are not bounds-checked. The next-frame validation only bounds-checks
STACK_FRAME_OVERHEAD, which does not include the pt_regs. Add another
test for this.

The user could set r1 to be equal to the address matching the first
interrupt frame - STACK_INT_FRAME_SIZE, which is in the previous page
due to the kernel redzone, and induce the kernel to load the marker from
there. Possibly this could cause a crash at least. If the user could
induce the previous page to contain a valid marker, then it might be
able to direct perf to read specific memory addresses in a way that
could be transmitted back to the user in the perf data.

Fixes: 20002ded4d93 ("perf_counter: powerpc: Add callchain support")
Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221127124942.1665522-4-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 32c5209214bd8d4f8c4e9d9b630ef4c671f58e79 ]

The interrupt frame detection and loads from the hypothetical pt_regs
are not bounds-checked. The next-frame validation only bounds-checks
STACK_FRAME_OVERHEAD, which does not include the pt_regs. Add another
test for this.

The user could set r1 to be equal to the address matching the first
interrupt frame - STACK_INT_FRAME_SIZE, which is in the previous page
due to the kernel redzone, and induce the kernel to load the marker from
there. Possibly this could cause a crash at least. If the user could
induce the previous page to contain a valid marker, then it might be
able to direct perf to read specific memory addresses in a way that
could be transmitted back to the user in the perf data.

Fixes: 20002ded4d93 ("perf_counter: powerpc: Add callchain support")
Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221127124942.1665522-4-npiggin@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/xive: add missing iounmap() in error path in xive_spapr_populate_irq_data()</title>
<updated>2023-01-18T10:41:30+00:00</updated>
<author>
<name>Yang Yingliang</name>
<email>yangyingliang@huawei.com</email>
</author>
<published>2022-10-17T03:23:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cfb5bbfcb63b25e9b6bbeb3206ffffd96f12d508'/>
<id>cfb5bbfcb63b25e9b6bbeb3206ffffd96f12d508</id>
<content type='text'>
[ Upstream commit 8b49670f3bb3f10cd4d5a6dca17f5a31b173ecdc ]

If remapping 'data-&gt;trig_page' fails, the 'data-&gt;eoi_mmio' need be unmapped
before returning from xive_spapr_populate_irq_data().

Fixes: eac1e731b59e ("powerpc/xive: guest exploitation of the XIVE interrupt controller")
Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Reviewed-by: Cédric Le Goater &lt;clg@kaod.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221017032333.1852406-1-yangyingliang@huawei.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 8b49670f3bb3f10cd4d5a6dca17f5a31b173ecdc ]

If remapping 'data-&gt;trig_page' fails, the 'data-&gt;eoi_mmio' need be unmapped
before returning from xive_spapr_populate_irq_data().

Fixes: eac1e731b59e ("powerpc/xive: guest exploitation of the XIVE interrupt controller")
Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Reviewed-by: Cédric Le Goater &lt;clg@kaod.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221017032333.1852406-1-yangyingliang@huawei.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/52xx: Fix a resource leak in an error handling path</title>
<updated>2023-01-18T10:41:30+00:00</updated>
<author>
<name>Christophe JAILLET</name>
<email>christophe.jaillet@wanadoo.fr</email>
</author>
<published>2022-01-29T07:16:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9bf842ffdd216b9f94d5b051b5d8b815f2426538'/>
<id>9bf842ffdd216b9f94d5b051b5d8b815f2426538</id>
<content type='text'>
[ Upstream commit 5836947613ef33d311b4eff6a32d019580a214f5 ]

The error handling path of mpc52xx_lpbfifo_probe() has a request_irq()
that is not balanced by a corresponding free_irq().

Add the missing call, as already done in the remove function.

Fixes: 3c9059d79f5e ("powerpc/5200: add LocalPlus bus FIFO device driver")
Signed-off-by: Christophe JAILLET &lt;christophe.jaillet@wanadoo.fr&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/dec1496d46ccd5311d0f6e9f9ca4238be11bf6a6.1643440531.git.christophe.jaillet@wanadoo.fr
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 5836947613ef33d311b4eff6a32d019580a214f5 ]

The error handling path of mpc52xx_lpbfifo_probe() has a request_irq()
that is not balanced by a corresponding free_irq().

Add the missing call, as already done in the remove function.

Fixes: 3c9059d79f5e ("powerpc/5200: add LocalPlus bus FIFO device driver")
Signed-off-by: Christophe JAILLET &lt;christophe.jaillet@wanadoo.fr&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/dec1496d46ccd5311d0f6e9f9ca4238be11bf6a6.1643440531.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
