linux.git/arch/s390/kernel/setup.c, branch v5.10.258

s390/archrandom: simplify back to earlier design and initialize earlier

2022-07-07T15:52:16+00:00

commit e4f74400308cb8abde5fdc9cad609c2aba32110c upstream.

s390x appears to present two RNG interfaces:
- a "TRNG" that gathers entropy using some hardware function; and
- a "DRBG" that takes in a seed and expands it.

Previously, the TRNG was wired up to arch_get_random_{long,int}(), but
it was observed that this was being called really frequently, resulting
in high overhead. So it was changed to be wired up to arch_get_random_
seed_{long,int}(), which was a reasonable decision. Later on, the DRBG
was then wired up to arch_get_random_{long,int}(), with a complicated
buffer filling thread, to control overhead and rate.

Fortunately, none of the performance issues matter much now. The RNG
always attempts to use arch_get_random_seed_{long,int}() first, which
means a complicated implementation of arch_get_random_{long,int}() isn't
really valuable or useful to have around. And it's only used when
reseeding, which means it won't hit the high throughput complications
that were faced before.

So this commit returns to an earlier design of just calling the TRNG in
arch_get_random_seed_{long,int}(), and returning false in arch_get_
random_{long,int}().

Part of what makes the simplification possible is that the RNG now seeds
itself using the TRNG at bootup. But this only works if the TRNG is
detected early in boot, before random_init() is called. So this commit
also causes that check to happen in setup_arch().

Cc: stable@vger.kernel.org
Cc: Harald Freudenberger 
Cc: Ingo Franzki 
Cc: Juergen Christ 
Cc: Heiko Carstens 
Signed-off-by: Jason A. Donenfeld 
Link: https://lore.kernel.org/r/20220610222023.378448-1-Jason@zx2c4.com
Reviewed-by: Harald Freudenberger 
Acked-by: Heiko Carstens 
Signed-off-by: Alexander Gordeev 
Signed-off-by: Jason A. Donenfeld 
Signed-off-by: Greg Kroah-Hartman

s390/setup: avoid using memblock_enforce_memory_limit

2021-12-08T08:03:19+00:00

[ Upstream commit 5dbc4cb4667457b0c53bcd7bff11500b3c362975 ]

There is a difference in how architectures treat "mem=" option. For some
that is an amount of online memory, for s390 and x86 this is the limiting
max address. Some memblock api like memblock_enforce_memory_limit()
take limit argument and explicitly treat it as the size of online memory,
and use __find_max_addr to convert it to an actual max address. Current
s390 usage:

memblock_enforce_memory_limit(memblock_end_of_DRAM());

yields different results depending on presence of memory holes (offline
memory blocks in between online memory). If there are no memory holes
limit == max_addr in memblock_enforce_memory_limit() and it does trim
online memory and reserved memory regions. With memory holes present it
actually does nothing.

Since we already use memblock_remove() explicitly to trim online memory
regions to potential limit (think mem=, kdump, addressing limits, etc.)
drop the usage of memblock_enforce_memory_limit() altogether. Trimming
reserved regions should not be required, since we now use
memblock_set_current_limit() to limit allocations and any explicit memory
reservations above the limit is an actual problem we should not hide.

Reviewed-by: Heiko Carstens 
Signed-off-by: Vasily Gorbik 
Signed-off-by: Heiko Carstens 
Signed-off-by: Sasha Levin

s390/sclp_vt220: fix console name to match device

2021-07-20T14:05:42+00:00

[ Upstream commit b7d91d230a119fdcc334d10c9889ce9c5e15118b ]

Console name reported in /proc/consoles:

  ttyS1                -W- (EC p  )    4:65

does not match the char device name:

  crw--w----    1 root     root        4,  65 May 17 12:18 /dev/ttysclp0

so debian-installer inside a QEMU s390x instance gets confused and fails
to start with the following error:

  steal-ctty: No such file or directory

Signed-off-by: Valentin Vidic 
Link: https://lore.kernel.org/r/20210427194010.9330-1-vvidic@valentin-vidic.from.hr
Signed-off-by: Christian Borntraeger 
Signed-off-by: Vasily Gorbik 
Signed-off-by: Sasha Levin

s390: preempt: Fix preempt_count initialization

2021-07-14T14:56:54+00:00

commit 6a942f5780545ebd11aca8b3ac4b163397962322 upstream.

S390's init_idle_preempt_count(p, cpu) doesn't actually let us initialize the
preempt_count of the requested CPU's idle task: it unconditionally writes
to the current CPU's. This clearly conflicts with idle_threads_init(),
which intends to initialize *all* the idle tasks, including their
preempt_count (or their CPU's, if the arch uses a per-CPU preempt_count).

Unfortunately, it seems the way s390 does things doesn't let us initialize
every possible CPU's preempt_count early on, as the pages where this
resides are only allocated when a CPU is brought up and are freed when it
is brought down.

Let the arch-specific code set a CPU's preempt_count when its lowcore is
allocated, and turn init_idle_preempt_count() into an empty stub.

Fixes: f1a0a376ca0c ("sched/core: Initialize the idle task with preemption disabled")
Reported-by: Guenter Roeck 
Signed-off-by: Valentin Schneider 
Tested-by: Guenter Roeck 
Reviewed-by: Heiko Carstens 
Link: https://lore.kernel.org/r/20210707163338.1623014-1-valentin.schneider@arm.com
Signed-off-by: Vasily Gorbik 
Signed-off-by: Greg Kroah-Hartman

s390: fix detection of vector enhancements facility 1 vs. vector packed decimal facility

2021-05-14T07:50:03+00:00

commit b208108638c4bd3215792415944467c36f5dfd97 upstream.

The PoP documents:
	134: The vector packed decimal facility is installed in the
	     z/Architecture architectural mode. When bit 134 is
	     one, bit 129 is also one.
	135: The vector enhancements facility 1 is installed in
	     the z/Architecture architectural mode. When bit 135
	     is one, bit 129 is also one.

Looks like we confuse the vector enhancements facility 1 ("EXT") with the
Vector packed decimal facility ("BCD"). Let's fix the facility checks.

Detected while working on QEMU/tcg z14 support and only unlocking
the vector enhancements facility 1, but not the vector packed decimal
facility.

Fixes: 2583b848cad0 ("s390: report new vector facilities")
Cc: Vasily Gorbik 
Signed-off-by: David Hildenbrand 
Reviewed-by: Christian Borntraeger 
Reviewed-by: Cornelia Huck 
Reviewed-by: Janosch Frank 
Link: https://lore.kernel.org/r/20210503121244.25232-1-david@redhat.com
Signed-off-by: Heiko Carstens 
Signed-off-by: Greg Kroah-Hartman

Merge tag 's390-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2020-10-16T19:36:38+00:00

Pull s390 updates from Vasily Gorbik:

 - Remove address space overrides using set_fs()

 - Convert to generic vDSO

 - Convert to generic page table dumper

 - Add ARCH_HAS_DEBUG_WX support

 - Add leap seconds handling support

 - Add NVMe firmware-assisted kernel dump support

 - Extend NVMe boot support with memory clearing control and addition of
   kernel parameters

 - AP bus and zcrypt api code rework. Add adapter configure/deconfigure
   interface. Extend debug features. Add failure injection support

 - Add ECC secure private keys support

 - Add KASan support for running protected virtualization host with
   4-level paging

 - Utilize destroy page ultravisor call to speed up secure guests
   shutdown

 - Implement ioremap_wc() and ioremap_prot() with MIO in PCI code

 - Various checksum improvements

 - Other small various fixes and improvements all over the code

* tag 's390-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (85 commits)
  s390/uaccess: fix indentation
  s390/uaccess: add default cases for __put_user_fn()/__get_user_fn()
  s390/zcrypt: fix wrong format specifications
  s390/kprobes: move insn_page to text segment
  s390/sie: fix typo in SIGP code description
  s390/lib: fix kernel doc for memcmp()
  s390/zcrypt: Introduce Failure Injection feature
  s390/zcrypt: move ap_msg param one level up the call chain
  s390/ap/zcrypt: revisit ap and zcrypt error handling
  s390/ap: Support AP card SCLP config and deconfig operations
  s390/sclp: Add support for SCLP AP adapter config/deconfig
  s390/ap: add card/queue deconfig state
  s390/ap: add error response code field for ap queue devices
  s390/ap: split ap queue state machine state from device state
  s390/zcrypt: New config switch CONFIG_ZCRYPT_DEBUG
  s390/zcrypt: introduce msg tracking in zcrypt functions
  s390/startup: correct early pgm check info formatting
  s390: remove orphaned extern variables declarations
  s390/kasan: make sure int handler always run with DAT on
  s390/ipl: add support to control memory clearing for nvme re-IPL
  ...

Merge tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping

2020-10-15T21:43:29+00:00

Pull dma-mapping updates from Christoph Hellwig:

 - rework the non-coherent DMA allocator

 - move private definitions out of 

 - lower CMA_ALIGNMENT (Paul Cercueil)

 - remove the omap1 dma address translation in favor of the common code

 - make dma-direct aware of multiple dma offset ranges (Jim Quinlan)

 - support per-node DMA CMA areas (Barry Song)

 - increase the default seg boundary limit (Nicolin Chen)

 - misc fixes (Robin Murphy, Thomas Tai, Xu Wang)

 - various cleanups

* tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping: (63 commits)
  ARM/ixp4xx: add a missing include of dma-map-ops.h
  dma-direct: simplify the DMA_ATTR_NO_KERNEL_MAPPING handling
  dma-direct: factor out a dma_direct_alloc_from_pool helper
  dma-direct check for highmem pages in dma_direct_alloc_pages
  dma-mapping: merge  into 
  dma-mapping: move large parts of  to kernel/dma
  dma-mapping: move dma-debug.h to kernel/dma/
  dma-mapping: remove 
  dma-mapping: merge  into 
  dma-contiguous: remove dma_contiguous_set_default
  dma-contiguous: remove dev_set_cma_area
  dma-contiguous: remove dma_declare_contiguous
  dma-mapping: split 
  cma: decrease CMA_ALIGNMENT lower limit to 2
  firewire-ohci: use dma_alloc_pages
  dma-iommu: implement ->alloc_noncoherent
  dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods
  dma-mapping: add a new dma_alloc_pages API
  dma-mapping: remove dma_cache_sync
  53c700: convert to dma_alloc_noncoherent
  ...

arch, drivers: replace for_each_membock() with for_each_mem_range()

2020-10-14T01:38:35+00:00

There are several occurrences of the following pattern:

	for_each_memblock(memory, reg) {
		start = __pfn_to_phys(memblock_region_memory_base_pfn(reg);
		end = __pfn_to_phys(memblock_region_memory_end_pfn(reg));

		/* do something with start and end */
	}

Using for_each_mem_range() iterator is more appropriate in such cases and
allows simpler and cleaner code.

[akpm@linux-foundation.org: fix arch/arm/mm/pmsa-v7.c build]
[rppt@linux.ibm.com: mips: fix cavium-octeon build caused by memblock refactoring]
  Link: http://lkml.kernel.org/r/20200827124549.GD167163@linux.ibm.com

Signed-off-by: Mike Rapoport 
Signed-off-by: Andrew Morton 
Cc: Andy Lutomirski 
Cc: Baoquan He 
Cc: Benjamin Herrenschmidt 
Cc: Borislav Petkov 
Cc: Catalin Marinas 
Cc: Christoph Hellwig 
Cc: Daniel Axtens 
Cc: Dave Hansen 
Cc: Emil Renner Berthing 
Cc: Hari Bathini 
Cc: Ingo Molnar 
Cc: Ingo Molnar 
Cc: Jonathan Cameron 
Cc: Marek Szyprowski 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Miguel Ojeda 
Cc: Palmer Dabbelt 
Cc: Paul Mackerras 
Cc: Paul Walmsley 
Cc: Peter Zijlstra 
Cc: Russell King 
Cc: Stafford Horne 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Link: https://lkml.kernel.org/r/20200818151634.14343-13-rppt@kernel.org
Signed-off-by: Linus Torvalds

memblock: make memblock_debug and related functionality private

2020-10-14T01:38:35+00:00

The only user of memblock_dbg() outside memblock was s390 setup code and
it is converted to use pr_debug() instead.  This allows to stop exposing
memblock_debug and memblock_dbg() to the rest of the kernel.

[akpm@linux-foundation.org: make memblock_dbg() safer and neater]

Signed-off-by: Mike Rapoport 
Signed-off-by: Andrew Morton 
Reviewed-by: Baoquan He 
Cc: Andy Lutomirski 
Cc: Benjamin Herrenschmidt 
Cc: Borislav Petkov 
Cc: Catalin Marinas 
Cc: Christoph Hellwig 
Cc: Daniel Axtens 
Cc: Dave Hansen 
Cc: Emil Renner Berthing 
Cc: Hari Bathini 
Cc: Ingo Molnar 
Cc: Ingo Molnar 
Cc: Jonathan Cameron 
Cc: Marek Szyprowski 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Miguel Ojeda 
Cc: Palmer Dabbelt 
Cc: Paul Mackerras 
Cc: Paul Walmsley 
Cc: Peter Zijlstra 
Cc: Russell King 
Cc: Stafford Horne 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Link: https://lkml.kernel.org/r/20200818151634.14343-10-rppt@kernel.org
Signed-off-by: Linus Torvalds

dma-mapping: merge into

2020-10-06T05:07:04+00:00

Merge dma-contiguous.h into dma-map-ops.h, after removing the comment
describing the contiguous allocator into kernel/dma/contigous.c.

Signed-off-by: Christoph Hellwig