linux-stable.git/arch/powerpc/kernel, branch v4.9.151 Linux kernel stable tree powerpc/tm: Set MSR[TS] just prior to recheckpoint 2019-01-13T09:03:52+00:00 Breno Leitao leitao@debian.org 2018-11-21T19:21:09+00:00 49edda5952ae2ba72a78dbfd24946f0d91370ccd commit e1c3743e1a20647c53b719dbf28b48f45d23f2cd upstream. On a signal handler return, the user could set a context with MSR[TS] bits set, and these bits would be copied to task regs->msr. At restore_tm_sigcontexts(), after current task regs->msr[TS] bits are set, several __get_user() are called and then a recheckpoint is executed. This is a problem since a page fault (in kernel space) could happen when calling __get_user(). If it happens, the process MSR[TS] bits were already set, but recheckpoint was not executed, and SPRs are still invalid. The page fault can cause the current process to be de-scheduled, with MSR[TS] active and without tm_recheckpoint() being called. More importantly, without TEXASR[FS] bit set also. Since TEXASR might not have the FS bit set, and when the process is scheduled back, it will try to reclaim, which will be aborted because of the CPU is not in the suspended state, and, then, recheckpoint. This recheckpoint will restore thread->texasr into TEXASR SPR, which might be zero, hitting a BUG_ON(). kernel BUG at /build/linux-sf3Co9/linux-4.9.30/arch/powerpc/kernel/tm.S:434! cpu 0xb: Vector: 700 (Program Check) at [c00000041f1576d0] pc: c000000000054550: restore_gprs+0xb0/0x180 lr: 0000000000000000 sp: c00000041f157950 msr: 8000000100021033 current = 0xc00000041f143000 paca = 0xc00000000fb86300 softe: 0 irq_happened: 0x01 pid = 1021, comm = kworker/11:1 kernel BUG at /build/linux-sf3Co9/linux-4.9.30/arch/powerpc/kernel/tm.S:434! Linux version 4.9.0-3-powerpc64le (debian-kernel@lists.debian.org) (gcc version 6.3.0 20170516 (Debian 6.3.0-18) ) #1 SMP Debian 4.9.30-2+deb9u2 (2017-06-26) enter ? for help [c00000041f157b30] c00000000001bc3c tm_recheckpoint.part.11+0x6c/0xa0 [c00000041f157b70] c00000000001d184 __switch_to+0x1e4/0x4c0 [c00000041f157bd0] c00000000082eeb8 __schedule+0x2f8/0x990 [c00000041f157cb0] c00000000082f598 schedule+0x48/0xc0 [c00000041f157ce0] c0000000000f0d28 worker_thread+0x148/0x610 [c00000041f157d80] c0000000000f96b0 kthread+0x120/0x140 [c00000041f157e30] c00000000000c0e0 ret_from_kernel_thread+0x5c/0x7c This patch simply delays the MSR[TS] set, so, if there is any page fault in the __get_user() section, it does not have regs->msr[TS] set, since the TM structures are still invalid, thus avoiding doing TM operations for in-kernel exceptions and possible process reschedule. With this patch, the MSR[TS] will only be set just before recheckpointing and setting TEXASR[FS] = 1, thus avoiding an interrupt with TM registers in invalid state. Other than that, if CONFIG_PREEMPT is set, there might be a preemption just after setting MSR[TS] and before tm_recheckpoint(), thus, this block must be atomic from a preemption perspective, thus, calling preempt_disable/enable() on this code. It is not possible to move tm_recheckpoint to happen earlier, because it is required to get the checkpointed registers from userspace, with __get_user(), thus, the only way to avoid this undesired behavior is delaying the MSR[TS] set. The 32-bits signal handler seems to be safe this current issue, but, it might be exposed to the preemption issue, thus, disabling preemption in this chunk of code. Changes from v2: * Run the critical section with preempt_disable. Fixes: 87b4e5393af7 ("powerpc/tm: Fix return of active 64bit signals") Cc: stable@vger.kernel.org (v3.9+) Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e1c3743e1a20647c53b719dbf28b48f45d23f2cd upstream.

On a signal handler return, the user could set a context with MSR[TS] bits
set, and these bits would be copied to task regs->msr.

At restore_tm_sigcontexts(), after current task regs->msr[TS] bits are set,
several __get_user() are called and then a recheckpoint is executed.

This is a problem since a page fault (in kernel space) could happen when
calling __get_user(). If it happens, the process MSR[TS] bits were
already set, but recheckpoint was not executed, and SPRs are still invalid.

The page fault can cause the current process to be de-scheduled, with
MSR[TS] active and without tm_recheckpoint() being called.  More
importantly, without TEXASR[FS] bit set also.

Since TEXASR might not have the FS bit set, and when the process is
scheduled back, it will try to reclaim, which will be aborted because of
the CPU is not in the suspended state, and, then, recheckpoint. This
recheckpoint will restore thread->texasr into TEXASR SPR, which might be
zero, hitting a BUG_ON().

	kernel BUG at /build/linux-sf3Co9/linux-4.9.30/arch/powerpc/kernel/tm.S:434!
	cpu 0xb: Vector: 700 (Program Check) at [c00000041f1576d0]
	    pc: c000000000054550: restore_gprs+0xb0/0x180
	    lr: 0000000000000000
	    sp: c00000041f157950
	   msr: 8000000100021033
	  current = 0xc00000041f143000
	  paca    = 0xc00000000fb86300	 softe: 0	 irq_happened: 0x01
	    pid   = 1021, comm = kworker/11:1
	kernel BUG at /build/linux-sf3Co9/linux-4.9.30/arch/powerpc/kernel/tm.S:434!
	Linux version 4.9.0-3-powerpc64le (debian-kernel@lists.debian.org) (gcc version 6.3.0 20170516 (Debian 6.3.0-18) ) #1 SMP Debian 4.9.30-2+deb9u2 (2017-06-26)
	enter ? for help
	[c00000041f157b30] c00000000001bc3c tm_recheckpoint.part.11+0x6c/0xa0
	[c00000041f157b70] c00000000001d184 __switch_to+0x1e4/0x4c0
	[c00000041f157bd0] c00000000082eeb8 __schedule+0x2f8/0x990
	[c00000041f157cb0] c00000000082f598 schedule+0x48/0xc0
	[c00000041f157ce0] c0000000000f0d28 worker_thread+0x148/0x610
	[c00000041f157d80] c0000000000f96b0 kthread+0x120/0x140
	[c00000041f157e30] c00000000000c0e0 ret_from_kernel_thread+0x5c/0x7c

This patch simply delays the MSR[TS] set, so, if there is any page fault in
the __get_user() section, it does not have regs->msr[TS] set, since the TM
structures are still invalid, thus avoiding doing TM operations for
in-kernel exceptions and possible process reschedule.

With this patch, the MSR[TS] will only be set just before recheckpointing
and setting TEXASR[FS] = 1, thus avoiding an interrupt with TM registers in
invalid state.

Other than that, if CONFIG_PREEMPT is set, there might be a preemption just
after setting MSR[TS] and before tm_recheckpoint(), thus, this block must
be atomic from a preemption perspective, thus, calling
preempt_disable/enable() on this code.

It is not possible to move tm_recheckpoint to happen earlier, because it is
required to get the checkpointed registers from userspace, with
__get_user(), thus, the only way to avoid this undesired behavior is
delaying the MSR[TS] set.

The 32-bits signal handler seems to be safe this current issue, but, it
might be exposed to the preemption issue, thus, disabling preemption in
this chunk of code.

Changes from v2:
 * Run the critical section with preempt_disable.

Fixes: 87b4e5393af7 ("powerpc/tm: Fix return of active 64bit signals")
Cc: stable@vger.kernel.org (v3.9+)
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/msi: Fix NULL pointer access in teardown code 2018-12-21T13:11:32+00:00 Radu Rendec radu.rendec@gmail.com 2018-11-28T03:20:48+00:00 b0daf4e6324f5164f91d8b9fcb4530e2928faf00 commit 78e7b15e17ac175e7eed9e21c6f92d03d3b0a6fa upstream. The arch_teardown_msi_irqs() function assumes that controller ops pointers were already checked in arch_setup_msi_irqs(), but this assumption is wrong: arch_teardown_msi_irqs() can be called even when arch_setup_msi_irqs() returns an error (-ENOSYS). This can happen in the following scenario: - msi_capability_init() calls pci_msi_setup_msi_irqs() - pci_msi_setup_msi_irqs() returns -ENOSYS - msi_capability_init() notices the error and calls free_msi_irqs() - free_msi_irqs() calls pci_msi_teardown_msi_irqs() This is easier to see when CONFIG_PCI_MSI_IRQ_DOMAIN is not set and pci_msi_setup_msi_irqs() and pci_msi_teardown_msi_irqs() are just aliases to arch_setup_msi_irqs() and arch_teardown_msi_irqs(). The call to free_msi_irqs() upon pci_msi_setup_msi_irqs() failure seems legit, as it does additional cleanup; e.g. list_del(&entry->list) and kfree(entry) inside free_msi_irqs() do happen (MSI descriptors are allocated before pci_msi_setup_msi_irqs() is called and need to be cleaned up if that fails). Fixes: 6b2fd7efeb88 ("PCI/MSI/PPC: Remove arch_msi_check_device()") Cc: stable@vger.kernel.org # v3.18+ Signed-off-by: Radu Rendec <radu.rendec@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 78e7b15e17ac175e7eed9e21c6f92d03d3b0a6fa upstream.

The arch_teardown_msi_irqs() function assumes that controller ops
pointers were already checked in arch_setup_msi_irqs(), but this
assumption is wrong: arch_teardown_msi_irqs() can be called even when
arch_setup_msi_irqs() returns an error (-ENOSYS).

This can happen in the following scenario:
  - msi_capability_init() calls pci_msi_setup_msi_irqs()
  - pci_msi_setup_msi_irqs() returns -ENOSYS
  - msi_capability_init() notices the error and calls free_msi_irqs()
  - free_msi_irqs() calls pci_msi_teardown_msi_irqs()

This is easier to see when CONFIG_PCI_MSI_IRQ_DOMAIN is not set and
pci_msi_setup_msi_irqs() and pci_msi_teardown_msi_irqs() are just
aliases to arch_setup_msi_irqs() and arch_teardown_msi_irqs().

The call to free_msi_irqs() upon pci_msi_setup_msi_irqs() failure
seems legit, as it does additional cleanup; e.g.
list_del(&entry->list) and kfree(entry) inside free_msi_irqs() do
happen (MSI descriptors are allocated before pci_msi_setup_msi_irqs()
is called and need to be cleaned up if that fails).

Fixes: 6b2fd7efeb88 ("PCI/MSI/PPC: Remove arch_msi_check_device()")
Cc: stable@vger.kernel.org # v3.18+
Signed-off-by: Radu Rendec <radu.rendec@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/eeh: Fix possible null deref in eeh_dump_dev_log() 2018-11-21T08:25:56+00:00 Sam Bobroff sbobroff@linux.ibm.com 2018-09-12T01:23:20+00:00 9bed31c93660e7af9caeebe8558d170e6f00e200 [ Upstream commit f9bc28aedfb5bbd572d2d365f3095c1becd7209b ] If an error occurs during an unplug operation, it's possible for eeh_dump_dev_log() to be called when edev->pdn is null, which currently leads to dereferencing a null pointer. Handle this by skipping the error log for those devices. Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit f9bc28aedfb5bbd572d2d365f3095c1becd7209b ]

If an error occurs during an unplug operation, it's possible for
eeh_dump_dev_log() to be called when edev->pdn is null, which
currently leads to dereferencing a null pointer.

Handle this by skipping the error log for those devices.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/tm: Avoid possible userspace r1 corruption on reclaim 2018-10-20T07:51:31+00:00 Michael Neuling mikey@neuling.org 2018-09-25T09:36:47+00:00 16b07d3af6402ede0ab3dbcf342a99e972fce8bc [ Upstream commit 96dc89d526ef77604376f06220e3d2931a0bfd58 ] Current we store the userspace r1 to PACATMSCRATCH before finally saving it to the thread struct. In theory an exception could be taken here (like a machine check or SLB miss) that could write PACATMSCRATCH and hence corrupt the userspace r1. The SLB fault currently doesn't touch PACATMSCRATCH, but others do. We've never actually seen this happen but it's theoretically possible. Either way, the code is fragile as it is. This patch saves r1 to the kernel stack (which can't fault) before we turn MSR[RI] back on. PACATMSCRATCH is still used but only with MSR[RI] off. We then copy r1 from the kernel stack to the thread struct once we have MSR[RI] back on. Suggested-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 96dc89d526ef77604376f06220e3d2931a0bfd58 ]

Current we store the userspace r1 to PACATMSCRATCH before finally
saving it to the thread struct.

In theory an exception could be taken here (like a machine check or
SLB miss) that could write PACATMSCRATCH and hence corrupt the
userspace r1. The SLB fault currently doesn't touch PACATMSCRATCH, but
others do.

We've never actually seen this happen but it's theoretically
possible. Either way, the code is fragile as it is.

This patch saves r1 to the kernel stack (which can't fault) before we
turn MSR[RI] back on. PACATMSCRATCH is still used but only with
MSR[RI] off. We then copy r1 from the kernel stack to the thread
struct once we have MSR[RI] back on.

Suggested-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/tm: Fix userspace r13 corruption 2018-10-20T07:51:31+00:00 Michael Neuling mikey@neuling.org 2018-09-24T07:27:04+00:00 42c08c3675b0b671f386d0168f3441f55dacb24a [ Upstream commit cf13435b730a502e814c63c84d93db131e563f5f ] When we treclaim we store the userspace checkpointed r13 to a scratch SPR and then later save the scratch SPR to the user thread struct. Unfortunately, this doesn't work as accessing the user thread struct can take an SLB fault and the SLB fault handler will write the same scratch SPRG that now contains the userspace r13. To fix this, we store r13 to the kernel stack (which can't fault) before we access the user thread struct. Found by running P8 guest + powervm + disable_1tb_segments + TM. Seen as a random userspace segfault with r13 looking like a kernel address. Signed-off-by: Michael Neuling <mikey@neuling.org> Reviewed-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit cf13435b730a502e814c63c84d93db131e563f5f ]

When we treclaim we store the userspace checkpointed r13 to a scratch
SPR and then later save the scratch SPR to the user thread struct.

Unfortunately, this doesn't work as accessing the user thread struct
can take an SLB fault and the SLB fault handler will write the same
scratch SPRG that now contains the userspace r13.

To fix this, we store r13 to the kernel stack (which can't fault)
before we access the user thread struct.

Found by running P8 guest + powervm + disable_1tb_segments + TM. Seen
as a random userspace segfault with r13 looking like a kernel address.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/fadump: Return error when fadump registration fails 2018-10-13T07:18:57+00:00 Michal Suchanek msuchanek@suse.de 2017-05-27T15:46:15+00:00 d3d39d256e52ee60a9faa9c33bdea23e9b27914a commit 98b8cd7f75643e0a442d7a4c1cef2c9d53b7e92b upstream. - log an error message when registration fails and no error code listed in the switch is returned - translate the hv error code to posix error code and return it from fw_register - return the posix error code from fw_register to the process writing to sysfs - return EEXIST on re-registration - return success on deregistration when fadump is not registered - return ENODEV when no memory is reserved for fadump Signed-off-by: Michal Suchanek <msuchanek@suse.de> Tested-by: Hari Bathini <hbathini@linux.vnet.ibm.com> [mpe: Use pr_err() to shrink the error print] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Kleber Sacilotto de Souza <kleber.souza@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 98b8cd7f75643e0a442d7a4c1cef2c9d53b7e92b upstream.

 - log an error message when registration fails and no error code listed
   in the switch is returned
 - translate the hv error code to posix error code and return it from
   fw_register
 - return the posix error code from fw_register to the process writing
   to sysfs
 - return EEXIST on re-registration
 - return success on deregistration when fadump is not registered
 - return ENODEV when no memory is reserved for fadump

Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Tested-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
[mpe: Use pr_err() to shrink the error print]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/kdump: Handle crashkernel memory reservation failure 2018-10-04T00:01:44+00:00 Hari Bathini hbathini@linux.ibm.com 2018-06-28T05:19:56+00:00 5735af39366ea69ce0e3fe02f24e92bb8760d80d [ Upstream commit 8950329c4a64c6d3ca0bc34711a1afbd9ce05657 ] Memory reservation for crashkernel could fail if there are holes around kdump kernel offset (128M). Fail gracefully in such cases and print an error message. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Tested-by: David Gibson <dgibson@redhat.com> Reviewed-by: Dave Young <dyoung@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 8950329c4a64c6d3ca0bc34711a1afbd9ce05657 ]

Memory reservation for crashkernel could fail if there are holes around
kdump kernel offset (128M). Fail gracefully in such cases and print an
error message.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Tested-by: David Gibson <dgibson@redhat.com>
Reviewed-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/fadump: handle crash memory ranges array index overflow 2018-09-09T18:01:20+00:00 Hari Bathini hbathini@linux.ibm.com 2018-08-06T20:42:45+00:00 1ae3174fb80704dfd8bbd7e6d73cf4fef033c2f4 commit 1bd6a1c4b80a28d975287630644e6b47d0f977a5 upstream. Crash memory ranges is an array of memory ranges of the crashing kernel to be exported as a dump via /proc/vmcore file. The size of the array is set based on INIT_MEMBLOCK_REGIONS, which works alright in most cases where memblock memory regions count is less than INIT_MEMBLOCK_REGIONS value. But this count can grow beyond INIT_MEMBLOCK_REGIONS value since commit 142b45a72e22 ("memblock: Add array resizing support"). On large memory systems with a few DLPAR operations, the memblock memory regions count could be larger than INIT_MEMBLOCK_REGIONS value. On such systems, registering fadump results in crash or other system failures like below: task: c00007f39a290010 ti: c00000000b738000 task.ti: c00000000b738000 NIP: c000000000047df4 LR: c0000000000f9e58 CTR: c00000000010f180 REGS: c00000000b73b570 TRAP: 0300 Tainted: G L X (4.4.140+) MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 22004484 XER: 20000000 CFAR: c000000000008500 DAR: 000007a450000000 DSISR: 40000000 SOFTE: 0 ... NIP [c000000000047df4] smp_send_reschedule+0x24/0x80 LR [c0000000000f9e58] resched_curr+0x138/0x160 Call Trace: resched_curr+0x138/0x160 (unreliable) check_preempt_curr+0xc8/0xf0 ttwu_do_wakeup+0x38/0x150 try_to_wake_up+0x224/0x4d0 __wake_up_common+0x94/0x100 ep_poll_callback+0xac/0x1c0 __wake_up_common+0x94/0x100 __wake_up_sync_key+0x70/0xa0 sock_def_readable+0x58/0xa0 unix_stream_sendmsg+0x2dc/0x4c0 sock_sendmsg+0x68/0xa0 ___sys_sendmsg+0x2cc/0x2e0 __sys_sendmsg+0x5c/0xc0 SyS_socketcall+0x36c/0x3f0 system_call+0x3c/0x100 as array index overflow is not checked for while setting up crash memory ranges causing memory corruption. To resolve this issue, dynamically allocate memory for crash memory ranges and resize it incrementally, in units of pagesize, on hitting array size limit. Fixes: 2df173d9e85d ("fadump: Initialize elfcore header and add PT_LOAD program headers.") Cc: stable@vger.kernel.org # v3.4+ Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> [mpe: Just use PAGE_SIZE directly, fixup variable placement] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 1bd6a1c4b80a28d975287630644e6b47d0f977a5 upstream.

Crash memory ranges is an array of memory ranges of the crashing kernel
to be exported as a dump via /proc/vmcore file. The size of the array
is set based on INIT_MEMBLOCK_REGIONS, which works alright in most cases
where memblock memory regions count is less than INIT_MEMBLOCK_REGIONS
value. But this count can grow beyond INIT_MEMBLOCK_REGIONS value since
commit 142b45a72e22 ("memblock: Add array resizing support").

On large memory systems with a few DLPAR operations, the memblock memory
regions count could be larger than INIT_MEMBLOCK_REGIONS value. On such
systems, registering fadump results in crash or other system failures
like below:

  task: c00007f39a290010 ti: c00000000b738000 task.ti: c00000000b738000
  NIP: c000000000047df4 LR: c0000000000f9e58 CTR: c00000000010f180
  REGS: c00000000b73b570 TRAP: 0300   Tainted: G          L   X  (4.4.140+)
  MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE>  CR: 22004484  XER: 20000000
  CFAR: c000000000008500 DAR: 000007a450000000 DSISR: 40000000 SOFTE: 0
  ...
  NIP [c000000000047df4] smp_send_reschedule+0x24/0x80
  LR [c0000000000f9e58] resched_curr+0x138/0x160
  Call Trace:
    resched_curr+0x138/0x160 (unreliable)
    check_preempt_curr+0xc8/0xf0
    ttwu_do_wakeup+0x38/0x150
    try_to_wake_up+0x224/0x4d0
    __wake_up_common+0x94/0x100
    ep_poll_callback+0xac/0x1c0
    __wake_up_common+0x94/0x100
    __wake_up_sync_key+0x70/0xa0
    sock_def_readable+0x58/0xa0
    unix_stream_sendmsg+0x2dc/0x4c0
    sock_sendmsg+0x68/0xa0
    ___sys_sendmsg+0x2cc/0x2e0
    __sys_sendmsg+0x5c/0xc0
    SyS_socketcall+0x36c/0x3f0
    system_call+0x3c/0x100

as array index overflow is not checked for while setting up crash memory
ranges causing memory corruption. To resolve this issue, dynamically
allocate memory for crash memory ranges and resize it incrementally,
in units of pagesize, on hitting array size limit.

Fixes: 2df173d9e85d ("fadump: Initialize elfcore header and add PT_LOAD program headers.")
Cc: stable@vger.kernel.org # v3.4+
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
[mpe: Just use PAGE_SIZE directly, fixup variable placement]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/8xx: fix invalid register expression in head_8xx.S 2018-08-03T05:55:19+00:00 Christophe Leroy christophe.leroy@c-s.fr 2018-05-24T11:02:06+00:00 38d96f7888f57f781e5ae80dde22ab97c1802e36 [ Upstream commit e4ccb1dae6bdef228d729c076c38161ef6e7ca34 ] New binutils generate the following warning AS arch/powerpc/kernel/head_8xx.o arch/powerpc/kernel/head_8xx.S: Assembler messages: arch/powerpc/kernel/head_8xx.S:916: Warning: invalid register expression This patch fixes it. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit e4ccb1dae6bdef228d729c076c38161ef6e7ca34 ]

New binutils generate the following warning

  AS      arch/powerpc/kernel/head_8xx.o
arch/powerpc/kernel/head_8xx.S: Assembler messages:
arch/powerpc/kernel/head_8xx.S:916: Warning: invalid register expression

This patch fixes it.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/32: Add a missing include header 2018-08-03T05:55:18+00:00 Mathieu Malaterre malat@debian.org 2018-03-22T20:20:03+00:00 ecd04c80fa32f7f111f676ab062bb621367cbf26 [ Upstream commit c89ca593220931c150cffda24b4d4ccf82f13fc8 ] The header file <linux/syscalls.h> was missing from the includes. Fix the following warning, treated as error with W=1: arch/powerpc/kernel/pci_32.c:286:6: error: no previous prototype for ‘sys_pciconfig_iobase’ [-Werror=missing-prototypes] Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit c89ca593220931c150cffda24b4d4ccf82f13fc8 ]

The header file <linux/syscalls.h> was missing from the includes. Fix the
following warning, treated as error with W=1:

  arch/powerpc/kernel/pci_32.c:286:6: error: no previous prototype for ‘sys_pciconfig_iobase’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>