Commit Graph

13 Commits

Author SHA1 Message Date
Peter Zijlstra b32fd8a60f x86,pm: Force out-of-line memcpy()
GCC fancies inlining memcpy(), and because it cannot prove the
destination is page-aligned (it is) it ends up generating atrocious
code like:

 19e:   48 8b 15 00 00 00 00    mov    0x0(%rip),%rdx        # 1a5 <relocate_restore_code+0x25> 1a1: R_X86_64_PC32      core_restore_code-0x4
 1a5:   48 8d 78 08             lea    0x8(%rax),%rdi
 1a9:   48 89 c1                mov    %rax,%rcx
 1ac:   48 c7 c6 00 00 00 00    mov    $0x0,%rsi        1af: R_X86_64_32S       core_restore_code
 1b3:   48 83 e7 f8             and    $0xfffffffffffffff8,%rdi
 1b7:   48 29 f9                sub    %rdi,%rcx
 1ba:   48 89 10                mov    %rdx,(%rax)
 1bd:   48 8b 15 00 00 00 00    mov    0x0(%rip),%rdx        # 1c4 <relocate_restore_code+0x44> 1c0: R_X86_64_PC32      core_restore_code+0xff4
 1c4:   48 29 ce                sub    %rcx,%rsi
 1c7:   81 c1 00 10 00 00       add    $0x1000,%ecx
 1cd:   48 89 90 f8 0f 00 00    mov    %rdx,0xff8(%rax)
 1d4:   c1 e9 03                shr    $0x3,%ecx
 1d7:   f3 48 a5                rep movsq %ds:(%rsi),%es:(%rdi)

Notably the alignment code generates a text reference to
code_restore_code+0xff8, for which objtool raises the objection:

  vmlinux.o: warning: objtool: relocate_restore_code+0x3d: relocation to !ENDBR: next_arg+0x18

Applying some __assume_aligned(PAGE_SIZE) improve code-gen to:

 19e:   48 89 c7                mov    %rax,%rdi
 1a1:   48 c7 c6 00 00 00 00    mov    $0x0,%rsi        1a4: R_X86_64_32S       core_restore_code
 1a8:   b9 00 02 00 00          mov    $0x200,%ecx
 1ad:   f3 48 a5                rep movsq %ds:(%rsi),%es:(%rdi)

And resolve the problem, however, none of this is important code and
a much simpler solution still is to force a memcpy() call:

 1a1:   ba 00 10 00 00          mov    $0x1000,%edx
 1a6:   48 c7 c6 00 00 00 00    mov    $0x0,%rsi        1a9: R_X86_64_32S       core_restore_code
 1ad:   e8 00 00 00 00          call   1b2 <relocate_restore_code+0x32> 1ae: R_X86_64_PLT32     __memcpy-0x4

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2022-11-05 11:28:02 +01:00
Chris von Recklinghausen f5d1499ae2 PM: hibernate: x86: Use crc32 instead of md5 for hibernation e820 integrity check
Hibernation fails on a system in fips mode because md5 is used for the e820
integrity check and is not available. Use crc32 instead.

The check is intended to detect whether the E820 memory map provided
by the firmware after cold boot unexpectedly differs from the one that
was in use when the hibernation image was created. In this case, the
hibernation image cannot be restored, as it may cover memory regions
that are no longer available to the OS.

A non-cryptographic checksum such as CRC-32 is sufficient to detect such
inadvertent deviations.

Fixes: 62a03defea ("PM / hibernate: Verify the consistent of e820 memory map by md5 digest")
Reviewed-by: Eric Biggers <ebiggers@google.com>
Tested-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>
[ rjw: Subject edit ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-04-21 19:03:37 +02:00
Waiman Long 453431a549 mm, treewide: rename kzfree() to kfree_sensitive()
As said by Linus:

  A symmetric naming is only helpful if it implies symmetries in use.
  Otherwise it's actively misleading.

  In "kzalloc()", the z is meaningful and an important part of what the
  caller wants.

  In "kzfree()", the z is actively detrimental, because maybe in the
  future we really _might_ want to use that "memfill(0xdeadbeef)" or
  something. The "zero" part of the interface isn't even _relevant_.

The main reason that kzfree() exists is to clear sensitive information
that should not be leaked to other future users of the same memory
objects.

Rename kzfree() to kfree_sensitive() to follow the example of the recently
added kvfree_sensitive() and make the intention of the API more explicit.
In addition, memzero_explicit() is used to clear the memory to make sure
that it won't get optimized away by the compiler.

The renaming is done by using the command sequence:

  git grep -w --name-only kzfree |\
  xargs sed -i 's/kzfree/kfree_sensitive/'

followed by some editing of the kfree_sensitive() kerneldoc and adding
a kzfree backward compatibility macro in slab.h.

[akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h]
[akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more]

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:22 -07:00
Mike Rapoport 65fddcfca8 mm: reorder includes after introduction of linux/pgtable.h
The replacement of <asm/pgrable.h> with <linux/pgtable.h> 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 <file> <header>" % (sys.argv[0])
	    sys.exit(1)

	hdr_to_move="#include <linux/%s>" % 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 <linux/"):
		    in_hdrs = True
		elif not moved and in_hdrs:
		    moved = True
		    print hdr_to_move
		print line

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Mike Rapoport ca5999fde0 mm: introduce include/linux/pgtable.h
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 <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Jiri Kosina ec527c3180 x86/power: Fix 'nosmt' vs hibernation triple fault during resume
As explained in

	0cc3cd2165 ("cpu/hotplug: Boot HT siblings at least once")

we always, no matter what, have to bring up x86 HT siblings during boot at
least once in order to avoid first MCE bringing the system to its knees.

That means that whenever 'nosmt' is supplied on the kernel command-line,
all the HT siblings are as a result sitting in mwait or cpudile after
going through the online-offline cycle at least once.

This causes a serious issue though when a kernel, which saw 'nosmt' on its
commandline, is going to perform resume from hibernation: if the resume
from the hibernated image is successful, cr3 is flipped in order to point
to the address space of the kernel that is being resumed, which in turn
means that all the HT siblings are all of a sudden mwaiting on address
which is no longer valid.

That results in triple fault shortly after cr3 is switched, and machine
reboots.

Fix this by always waking up all the SMT siblings before initiating the
'restore from hibernation' process; this guarantees that all the HT
siblings will be properly carried over to the resumed kernel waiting in
resume_play_dead(), and acted upon accordingly afterwards, based on the
target kernel configuration.

Symmetricaly, the resumed kernel has to push the SMT siblings to mwait
again in case it has SMT disabled; this means it has to online all
the siblings when resuming (so that they come out of hlt) and offline
them again to let them reach mwait.

Cc: 4.19+ <stable@vger.kernel.org> # v4.19+
Debugged-by: Thomas Gleixner <tglx@linutronix.de>
Fixes: 0cc3cd2165 ("cpu/hotplug: Boot HT siblings at least once")
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-06-03 12:02:03 +02:00
Eric Biggers 877b5691f2 crypto: shash - remove shash_desc::flags
The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.

With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP.  These would all need to be fixed if any shash algorithm
actually started sleeping.  For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API.  However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.

Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk.  It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.

Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-25 15:38:12 +08:00
Zhimin Gu 5331d2c7ef x86-32, hibernate: Set up temporary text mapping for 32bit system
Set up the temporary text mapping for the final jump address
so that the system could jump to the right address after all
the pages have been copied back to their original address -
otherwise the final mapping for the jump address is invalid.

Analogous changes were made for 64-bit in commit 65c0554b73
(x86/power/64: Fix kernel text mapping corruption during image
restoration).

Signed-off-by: Zhimin Gu <kookoo.gu@intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-10-03 11:56:34 +02:00
Zhimin Gu 6bae499a0a x86-32, hibernate: Switch to relocated restore code during resume on 32bit system
On 64bit system, code should be executed in a safe page
during page restoring, as the page where instruction is
running during resume might be scribbled and causes issues.

Although on 32 bit, we only suspend resuming by same kernel
that did the suspend, we'd like to remove that restriction
in the future.

Porting corresponding code from
64bit system: Allocate a safe page, and copy the restore
code to it, then jump to the safe page to run the code.

Signed-off-by: Zhimin Gu <kookoo.gu@intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-10-03 11:56:34 +02:00
Zhimin Gu 32aa276437 x86-32, hibernate: Switch to original page table after resumed
After all the pages are restored to previous address, the page
table switches back to current swapper_pg_dir. However the
swapper_pg_dir currently in used might not be consistent with
previous page table, which might cause issue after resume.

Fix this issue by switching to original page table after resume,
and the address of the original page table is saved in the hibernation
image header.

Move the manipulation of restore_cr3 into common code blocks.

Signed-off-by: Zhimin Gu <kookoo.gu@intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-10-03 11:56:34 +02:00
Zhimin Gu 72adf47764 x86, hibernate: Rename temp_level4_pgt to temp_pgt
As 32bit system is not using 4-level page, rename it
to temp_pgt so that it can be reused for both 32bit
and 64bit hibernation.

No functional change.

Signed-off-by: Zhimin Gu <kookoo.gu@intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-10-03 11:56:34 +02:00
Zhimin Gu 445565303d x86-32, hibernate: Enable CONFIG_ARCH_HIBERNATION_HEADER on 32bit system
Enable CONFIG_ARCH_HIBERNATION_HEADER for 32bit system so that

1. arch_hibernation_header_save/restore() are invoked across
   hibernation on 32bit system.

2. The checksum handling as well as 'magic' number checking
   for 32bit system are enabled.

Controlled by CONFIG_X86_64 in hibernate.c

Signed-off-by: Zhimin Gu <kookoo.gu@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-10-03 11:56:33 +02:00
Zhimin Gu 25862a049e x86, hibernate: Extract the common code of 64/32 bit system
Reduce the hibernation code duplication between x86-32 and x86-64
by extracting the common code into hibernate.c.

Currently only pfn_is_nosave() is the activated common
function in hibernate.c

No functional change.

Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Zhimin Gu <kookoo.gu@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-10-03 11:56:33 +02:00