<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-dev/arch/s390/boot/kaslr.c, branch linus/master</title>
<subtitle>Linux kernel development work - see feature branches</subtitle>
<id>https://git.zx2c4.com/linux-dev/atom/arch/s390/boot/kaslr.c?h=linus%2Fmaster</id>
<link rel='self' href='https://git.zx2c4.com/linux-dev/atom/arch/s390/boot/kaslr.c?h=linus%2Fmaster'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/'/>
<updated>2022-05-06T18:45:14Z</updated>
<entry>
<title>s390/boot: get rid of startup archive</title>
<updated>2022-05-06T18:45:14Z</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2022-04-23T19:31:22Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=edd4a8667355607345b76d5652adc0f300a28970'/>
<id>urn:sha1:edd4a8667355607345b76d5652adc0f300a28970</id>
<content type='text'>
The final kernel image is created by linking decompressor object files with
a startup archive. The startup archive file however does not contain only
optional code and data which can be discarded if not referenced. It also
contains mandatory object data like head.o which must never be discarded,
even if not referenced.

Move the decompresser code and linker script to the boot directory and get
rid of the startup archive so everything is kept during link time.

Acked-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>s390/boot: introduce boot data 'initrd_data'</title>
<updated>2021-07-27T07:39:15Z</updated>
<author>
<name>Alexander Egorenkov</name>
<email>egorenar@linux.ibm.com</email>
</author>
<published>2021-06-15T12:15:07Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=84733284f67b1a937f6205fdb16aa5cbb8b4f53d'/>
<id>urn:sha1:84733284f67b1a937f6205fdb16aa5cbb8b4f53d</id>
<content type='text'>
The new boot data struct shall replace global variables INITRD_START and
INITRD_SIZE. It is initialized in the decompressor and passed
to the decompressed kernel. In comparison to the old solution, this one
doesn't access data at fixed physical addresses which will become important
when the decompressor becomes relocatable.

Signed-off-by: Alexander Egorenkov &lt;egorenar@linux.ibm.com&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>s390: unify identity mapping limits handling</title>
<updated>2020-11-20T18:19:10Z</updated>
<author>
<name>Vasily Gorbik</name>
<email>gor@linux.ibm.com</email>
</author>
<published>2020-10-19T09:01:33Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=73045a08cf5549cc7dee14463431fbeb2134dd67'/>
<id>urn:sha1:73045a08cf5549cc7dee14463431fbeb2134dd67</id>
<content type='text'>
Currently we have to consider too many different values which
in the end only affect identity mapping size. These are:
1. max_physmem_end - end of physical memory online or standby.
   Always &lt;= end of the last online memory block (get_mem_detect_end()).
2. CONFIG_MAX_PHYSMEM_BITS - the maximum size of physical memory the
   kernel is able to support.
3. "mem=" kernel command line option which limits physical memory usage.
4. OLDMEM_BASE which is a kdump memory limit when the kernel is executed as
   crash kernel.
5. "hsa" size which is a memory limit when the kernel is executed during
   zfcp/nvme dump.

Through out kernel startup and run we juggle all those values at once
but that does not bring any amusement, only confusion and complexity.

Unify all those values to a single one we should really care, that is
our identity mapping size.

Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Reviewed-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>s390/kasan: move memory needs estimation into a function</title>
<updated>2020-11-09T10:20:59Z</updated>
<author>
<name>Vasily Gorbik</name>
<email>gor@linux.ibm.com</email>
</author>
<published>2020-10-05T11:53:36Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=0c4ec024a481774df98910c79a4b3a105d1bb996'/>
<id>urn:sha1:0c4ec024a481774df98910c79a4b3a105d1bb996</id>
<content type='text'>
Also correct rounding downs in estimation calculations.

Reviewed-by: Alexander Egorenkov &lt;egorenar@linux.ibm.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>s390/kaslr: correct and explain randomization base generation</title>
<updated>2020-09-29T13:00:58Z</updated>
<author>
<name>Vasily Gorbik</name>
<email>gor@linux.ibm.com</email>
</author>
<published>2020-09-18T14:02:45Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=5c46f2768c4bbf8e0beebea9adac1320015816b7'/>
<id>urn:sha1:5c46f2768c4bbf8e0beebea9adac1320015816b7</id>
<content type='text'>
Currently there are several minor problems with randomization base
generation code:

1. It might misbehave in low memory conditions. In particular there
might be enough space for the kernel on [0, block_sum] but after
	if (base &lt; safe_addr)
		base = safe_addr;
it might not be enough anymore.

2. It does not correctly handle minimal address constraint. In condition
	if (base &lt; safe_addr)
		base = safe_addr;
a synthetic value is compared with an address. If we have a memory
setup with memory holes due to offline memory regions, and safe_addr is
close to the end of the first online memory block - we might position
the kernel in invalid memory.

3. block_sum calculation logic contains off-by-one error. Let's say we
have a memory block in which the kernel fits perfectly
(end - start == kernel_size). In this case:
		if (end - start &lt; kernel_size)
			continue;
		block_sum += end - start - kernel_size;
block_sum is not increased, while it is a valid kernel position.

So, address problems listed and explain algorithm used. Besides that
restructuring the code makes it possible to extend kernel positioning
algorithm further. Currently we pick position in between single
[min, max] range (min = safe_addr, max = memory_limit). In future we
can do that for multiple ranges as well (by calling
count_valid_kernel_positions for each range).

Reviewed-by: Philipp Rudo &lt;prudo@linux.ibm.com&gt;
Reviewed-by: Alexander Egorenkov &lt;egorenar@linux.ibm.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>s390/kaslr: avoid mixing valid random value and an error code</title>
<updated>2020-09-29T13:00:58Z</updated>
<author>
<name>Vasily Gorbik</name>
<email>gor@linux.ibm.com</email>
</author>
<published>2020-09-23T07:37:43Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=07a699bc43d1feb2abe3d47781e2db3d08554bcc'/>
<id>urn:sha1:07a699bc43d1feb2abe3d47781e2db3d08554bcc</id>
<content type='text'>
0 is a valid random value. To avoid mixing it with error code 0 as an
return code make get_random() take extra argument to output random
value and return an error code.

Reviewed-by: Philipp Rudo &lt;prudo@linux.ibm.com&gt;
Reviewed-by: Alexander Egorenkov &lt;egorenar@linux.ibm.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>mm: reorder includes after introduction of linux/pgtable.h</title>
<updated>2020-06-09T16:39:13Z</updated>
<author>
<name>Mike Rapoport</name>
<email>rppt@linux.ibm.com</email>
</author>
<published>2020-06-09T04:32:42Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=65fddcfca8ad14778f71a57672fd01e8112d30fa'/>
<id>urn:sha1:65fddcfca8ad14778f71a57672fd01e8112d30fa</id>
<content type='text'>
The replacement of &lt;asm/pgrable.h&gt; with &lt;linux/pgtable.h&gt; made the include
of the latter in the middle of asm includes.  Fix this up with the aid of
the below script and manual adjustments here and there.

	import sys
	import re

	if len(sys.argv) is not 3:
	    print "USAGE: %s &lt;file&gt; &lt;header&gt;" % (sys.argv[0])
	    sys.exit(1)

	hdr_to_move="#include &lt;linux/%s&gt;" % sys.argv[2]
	moved = False
	in_hdrs = False

	with open(sys.argv[1], "r") as f:
	    lines = f.readlines()
	    for _line in lines:
		line = _line.rstrip('
')
		if line == hdr_to_move:
		    continue
		if line.startswith("#include &lt;linux/"):
		    in_hdrs = True
		elif not moved and in_hdrs:
		    moved = True
		    print hdr_to_move
		print line

Signed-off-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Brian Cain &lt;bcain@codeaurora.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Greentime Hu &lt;green.hu@gmail.com&gt;
Cc: Greg Ungerer &lt;gerg@linux-m68k.org&gt;
Cc: Guan Xuetao &lt;gxt@pku.edu.cn&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Ley Foon Tan &lt;ley.foon.tan@intel.com&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Michal Simek &lt;monstr@monstr.eu&gt;
Cc: Nick Hu &lt;nickhu@andestech.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Richard Weinberger &lt;richard@nod.at&gt;
Cc: Rich Felker &lt;dalias@libc.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Stafford Horne &lt;shorne@gmail.com&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Vincent Chen &lt;deanbo422@gmail.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Yoshinori Sato &lt;ysato@users.sourceforge.jp&gt;
Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mm: introduce include/linux/pgtable.h</title>
<updated>2020-06-09T16:39:13Z</updated>
<author>
<name>Mike Rapoport</name>
<email>rppt@linux.ibm.com</email>
</author>
<published>2020-06-09T04:32:38Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=ca5999fde0a1761665a38e4c9a72dbcd7d190a81'/>
<id>urn:sha1:ca5999fde0a1761665a38e4c9a72dbcd7d190a81</id>
<content type='text'>
The include/linux/pgtable.h is going to be the home of generic page table
manipulation functions.

Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and
make the latter include asm/pgtable.h.

Signed-off-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Brian Cain &lt;bcain@codeaurora.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Greentime Hu &lt;green.hu@gmail.com&gt;
Cc: Greg Ungerer &lt;gerg@linux-m68k.org&gt;
Cc: Guan Xuetao &lt;gxt@pku.edu.cn&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Ley Foon Tan &lt;ley.foon.tan@intel.com&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Michal Simek &lt;monstr@monstr.eu&gt;
Cc: Nick Hu &lt;nickhu@andestech.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Richard Weinberger &lt;richard@nod.at&gt;
Cc: Rich Felker &lt;dalias@libc.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Stafford Horne &lt;shorne@gmail.com&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Vincent Chen &lt;deanbo422@gmail.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Yoshinori Sato &lt;ysato@users.sourceforge.jp&gt;
Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>s390/kaslr: Fix casts in get_random</title>
<updated>2020-02-17T17:01:58Z</updated>
<author>
<name>Nathan Chancellor</name>
<email>natechancellor@gmail.com</email>
</author>
<published>2020-02-08T14:10:52Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=788d671517b5c81efbed9310ccbadb8cca86a08e'/>
<id>urn:sha1:788d671517b5c81efbed9310ccbadb8cca86a08e</id>
<content type='text'>
Clang warns:

../arch/s390/boot/kaslr.c:78:25: warning: passing 'char *' to parameter
of type 'const u8 *' (aka 'const unsigned char *') converts between
pointers to integer
types with different sign [-Wpointer-sign]
                                  (char *) entropy, (char *) entropy,
                                                    ^~~~~~~~~~~~~~~~
../arch/s390/include/asm/cpacf.h:280:28: note: passing argument to
parameter 'src' here
                            u8 *dest, const u8 *src, long src_len)
                                                ^
2 warnings generated.

Fix the cast to match what else is done in this function.

Fixes: b2d24b97b2a9 ("s390/kernel: add support for kernel address space layout randomization (KASLR)")
Link: https://github.com/ClangBuiltLinux/linux/issues/862
Link: https://lkml.kernel.org/r/20200208141052.48476-1-natechancellor@gmail.com
Signed-off-by: Nathan Chancellor &lt;natechancellor@gmail.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>Merge tag 's390-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux</title>
<updated>2019-09-17T21:04:43Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-09-17T21:04:43Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=d590284419b1d7cc2dc646e9bdde4da19061cf0f'/>
<id>urn:sha1:d590284419b1d7cc2dc646e9bdde4da19061cf0f</id>
<content type='text'>
Pull s390 updates from Vasily Gorbik:

 - Add support for IBM z15 machines.

 - Add SHA3 and CCA AES cipher key support in zcrypt and pkey
   refactoring.

 - Move to arch_stack_walk infrastructure for the stack unwinder.

 - Various kasan fixes and improvements.

 - Various command line parsing fixes.

 - Improve decompressor phase debuggability.

 - Lift no bss usage restriction for the early code.

 - Use refcount_t for reference counters for couple of places in mm
   code.

 - Logging improvements and return code fix in vfio-ccw code.

 - Couple of zpci fixes and minor refactoring.

 - Remove some outdated documentation.

 - Fix secure boot detection.

 - Other various minor code clean ups.

* tag 's390-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (48 commits)
  s390: remove pointless drivers-y in drivers/s390/Makefile
  s390/cpum_sf: Fix line length and format string
  s390/pci: fix MSI message data
  s390: add support for IBM z15 machines
  s390/crypto: Support for SHA3 via CPACF (MSA6)
  s390/startup: add pgm check info printing
  s390/crypto: xts-aes-s390 fix extra run-time crypto self tests finding
  vfio-ccw: fix error return code in vfio_ccw_sch_init()
  s390: vfio-ap: fix warning reset not completed
  s390/base: remove unused s390_base_mcck_handler
  s390/sclp: Fix bit checked for has_sipl
  s390/zcrypt: fix wrong handling of cca cipher keygenflags
  s390/kasan: add kdump support
  s390/setup: avoid using strncmp with hardcoded length
  s390/sclp: avoid using strncmp with hardcoded length
  s390/module: avoid using strncmp with hardcoded length
  s390/pci: avoid using strncmp with hardcoded length
  s390/kaslr: reserve memory for kasan usage
  s390/mem_detect: provide single get_mem_detect_end
  s390/cmma: reuse kstrtobool for option value parsing
  ...
</content>
</entry>
</feed>
