linux.git/arch/parisc, branch v4.13

parisc: Define CONFIG_CPU_BIG_ENDIAN

2017-07-31T15:51:27+00:00

While working on enabling queued rwlock on SPARC, found this following
code in include/asm-generic/qrwlock.h which uses CONFIG_CPU_BIG_ENDIAN
to clear a byte.

static inline u8 *__qrwlock_write_byte(struct qrwlock *lock)
 {
	return (u8 *)lock + 3 * IS_BUILTIN(CONFIG_CPU_BIG_ENDIAN);
 }

Problem is many of the fixed big endian architectures don't define
CPU_BIG_ENDIAN and clears the wrong byte.

Define CPU_BIG_ENDIAN for parisc architecture to fix it.

Signed-off-by: Babu Moger 
Signed-off-by: Helge Deller

parisc: Increase thread and stack size to 32kb

2017-07-31T06:41:26+00:00

Since kernel 4.11 the thread and irq stacks on parisc randomly overflow
the default size of 16k. The reason why stack usage suddenly grew is yet
unknown.

Signed-off-by: Helge Deller 
Cc: stable@vger.kernel.org # 4.11+
Signed-off-by: Helge Deller

parisc: Handle vma's whose context is not current in flush_cache_range

2017-07-31T06:22:33+00:00

In testing James' patch to drivers/parisc/pdc_stable.c, I hit the BUG
statement in flush_cache_range() during a system shutdown:

kernel BUG at arch/parisc/kernel/cache.c:595!
CPU: 2 PID: 6532 Comm: kworker/2:0 Not tainted 4.13.0-rc2+ #1
Workqueue: events free_ioctx

 IAOQ[0]: flush_cache_range+0x144/0x148
 IAOQ[1]: flush_cache_page+0x0/0x1a8
 RP(r2): flush_cache_range+0xec/0x148
Backtrace:
 [<00000000402910ac>] unmap_page_range+0x84/0x880
 [<00000000402918f4>] unmap_single_vma+0x4c/0x60
 [<0000000040291a18>] zap_page_range_single+0x110/0x160
 [<0000000040291c34>] unmap_mapping_range+0x174/0x1a8
 [<000000004026ccd8>] truncate_pagecache+0x50/0xa8
 [<000000004026cd84>] truncate_setsize+0x54/0x70
 [<000000004033d534>] put_aio_ring_file+0x44/0xb0
 [<000000004033d5d8>] aio_free_ring+0x38/0x140
 [<000000004033d714>] free_ioctx+0x34/0xa8
 [<00000000401b0028>] process_one_work+0x1b8/0x4d0
 [<00000000401b04f4>] worker_thread+0x1b4/0x648
 [<00000000401b9128>] kthread+0x1b0/0x208
 [<0000000040150020>] end_fault_vector+0x20/0x28
 [<0000000040639518>] nf_ip_reroute+0x50/0xa8
 [<0000000040638ed0>] nf_ip_route+0x10/0x78
 [<0000000040638c90>] xfrm4_mode_tunnel_input+0x180/0x1f8

CPU: 2 PID: 6532 Comm: kworker/2:0 Not tainted 4.13.0-rc2+ #1
Workqueue: events free_ioctx
Backtrace:
 [<0000000040163bf0>] show_stack+0x20/0x38
 [<0000000040688480>] dump_stack+0xa8/0x120
 [<0000000040163dc4>] die_if_kernel+0x19c/0x2b0
 [<0000000040164d0c>] handle_interruption+0xa24/0xa48

This patch modifies flush_cache_range() to handle non current contexts.
In as much as this occurs infrequently, the simplest approach is to
flush the entire cache when this happens.

Signed-off-by: John David Anglin 
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Helge Deller

parisc: Extend disabled preemption in copy_user_page

2017-07-25T21:36:54+00:00

It's always bothered me that we only disable preemption in
copy_user_page around the call to flush_dcache_page_asm.
This patch extends this to after the copy.

Signed-off-by: John David Anglin 
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Helge Deller

parisc: Prevent TLB speculation on flushed pages on CPUs that only support equivalent aliases

2017-07-25T21:36:53+00:00

Helge noticed that we flush the TLB page in flush_cache_page but not in
flush_cache_range or flush_cache_mm.

For a long time, we have had random segmentation faults building
packages on machines with PA8800/8900 processors.  These machines only
support equivalent aliases.  We don't see these faults on machines that
don't require strict coherency.  So, it appears TLB speculation
sometimes leads to cache corruption on machines that require coherency.

This patch adds TLB flushes to flush_cache_range and flush_cache_mm when
coherency is required.  We only flush the TLB in flush_cache_page when
coherency is required.

The patch also optimizes flush_cache_range.  It turns out we always have
the right context to use flush_user_dcache_range_asm and
flush_user_icache_range_asm.

The patch has been tested for some time on rp3440, rp3410 and A500-44.
It's been boot tested on c8000.  No random segmentation faults were
observed during testing.

Signed-off-by: John David Anglin 
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Helge Deller

parisc: Suspend lockup detectors before system halt

2017-07-25T19:43:38+00:00

Some machines can't power off the machine, so disable the lockup detectors to
avoid this watchdog BUG to show up every few seconds:
watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [systemd-shutdow:1]

Signed-off-by: Helge Deller 
Cc: stable@vger.kernel.org # 4.9+

parisc: Show DIMM slot number which holds broken memory module

2017-07-25T19:43:10+00:00

The Page Deallocation Table (PDT) holds the physical addresses of all broken
memory addresses. With the physical address we now are able to show which DIMM
slot (e.g. 1a, 3c) actually holds the broken memory module so that users are
able to replace it.

Signed-off-by: Helge Deller

parisc: Add function to return DIMM slot of physical address

2017-07-25T17:28:37+00:00

Add a firmware wrapper function, which asks PDC firmware for the DIMM slot of a
physical address. This is needed to show users which DIMM module needs
replacement in case a broken DIMM was encountered.

Signed-off-by: Helge Deller

parisc: Fix crash when calling PDC_PAT_MEM PDT firmware function

2017-07-25T16:24:39+00:00

Commit c9c2877d08d9 ("parisc: Add Page Deallocation Table (PDT) support")
introduced the pdc_pat_mem_read_pd_pdt() firmware helper function, which
crashed the system because it trashed the stack if the
pdc_pat_mem_read_pd_retinfo struct was located on the stack (and which is
in size less than the required 32 64-bit values).

Fix it by using the pdc_result struct instead when calling firmware and copy
the return values back into the result struct when finished sucessfully.

While debugging this code I noticed that the pdc_type wasn't set correctly
either, so let's fix that too.

Fixes: c9c2877d08d9 ("parisc: Add Page Deallocation Table (PDT) support")
Signed-off-by: Helge Deller

parisc: regenerate defconfig files

2017-07-23T20:08:42+00:00

Signed-off-by: Helge Deller