commit f75d651587f719a813ebbbfeee570e6570731d55 upstream.

The first group of warnings is caused by a "/**" kernel-doc notation
marker but the function comments are not in kernel-doc format.
Also add another error return value here.

  ../kernel/resource.c:337: warning: Function parameter or member 'start' not described in 'find_next_iomem_res'
  ../kernel/resource.c:337: warning: Function parameter or member 'end' not described in 'find_next_iomem_res'
  ../kernel/resource.c:337: warning: Function parameter or member 'flags' not described in 'find_next_iomem_res'
  ../kernel/resource.c:337: warning: Function parameter or member 'desc' not described in 'find_next_iomem_res'
  ../kernel/resource.c:337: warning: Function parameter or member 'first_lvl' not described in 'find_next_iomem_res'
  ../kernel/resource.c:337: warning: Function parameter or member 'res' not described in 'find_next_iomem_res'

Add the missing function parameter documentation for the other warnings:

  ../kernel/resource.c:409: warning: Function parameter or member 'arg' not described in 'walk_iomem_res_desc'
  ../kernel/resource.c:409: warning: Function parameter or member 'func' not described in 'walk_iomem_res_desc'
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: b69c2e20f6e4 ("resource: Clean it up a bit")
Link: http://lkml.kernel.org/r/dda2e4d8-bedd-3167-20fe-8c7d2d35b354@infradead.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
[joseph: fix find_next_iomem_res() documentation]
Signed-off-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: NCaspar Zhang <caspar@linux.alibaba.com>

commit 2b539aefe9e48e3908cff02699aa63a8b9bd268e upstream

In the process of onlining memory, we use walk_system_ram_range()
to find the actual RAM areas inside of the area being onlined.

However, it currently only finds memory resources which are
"top-level" iomem_resources.  Children are not currently
searched which causes it to skip System RAM in areas like this
(in the format of /proc/iomem):

a0000000-bfffffff : Persistent Memory (legacy)
  a0000000-afffffff : System RAM

Changing the true->false here allows children to be searched
as well.  We need this because we add a new "System RAM"
resource underneath the "persistent memory" resource when
we use persistent memory in a volatile mode.
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: linux-nvdimm@lists.01.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: Huang Ying <ying.huang@intel.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
Reviewed-by: NGavin Shan <shan.gavin@linux.alibaba.com>

commit b926b7f3baecb2a855db629e6822e1a85212e91c upstream

HMM consumes physical address space for its own use, even
though nothing is mapped or accessible there.  It uses a
special resource description (IORES_DESC_DEVICE_PRIVATE_MEMORY)
to uniquely identify these areas.

When HMM consumes address space, it makes a best guess about
what to consume.  However, it is possible that a future memory
or device hotplug can collide with the reserved area.  In the
case of these conflicts, there is an error message in
register_memory_resource().

Later patches in this series move register_memory_resource()
from using request_resource_conflict() to __request_region().
Unfortunately, __request_region() does not return the conflict
like the previous function did, which makes it impossible to
check for IORES_DESC_DEVICE_PRIVATE_MEMORY in a conflicting
resource.

Instead of warning in register_memory_resource(), move the
check into the core resource code itself (__request_region())
where the conflicting resource _is_ available.  This has the
added bonus of producing a warning in case of HMM conflicts
with devices *or* RAM address space, as opposed to the RAM-
only warnings that were there previously.
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: NJerome Glisse <jglisse@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: linux-nvdimm@lists.01.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: Huang Ying <ying.huang@intel.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
Reviewed-by: NGavin Shan <shan.gavin@linux.alibaba.com>

commit 5cd401ace914dc68556c6d2fcae0c349444d5f86 upstream

walk_system_ram_range() can return an error code either becuase
*it* failed, or because the 'func' that it calls returned an
error.  The memory hotplug does the following:

	ret = walk_system_ram_range(..., func);
        if (ret)
		return ret;

and 'ret' makes it out to userspace, eventually.  The problem
s, walk_system_ram_range() failues that result from *it* failing
(as opposed to 'func') return -1.  That leads to a very odd
-EPERM (-1) return code out to userspace.

Make walk_system_ram_range() return -EINVAL for internal
failures to keep userspace less confused.

This return code is compatible with all the callers that I
audited.
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: linux-nvdimm@lists.01.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: Huang Ying <ying.huang@intel.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Keith Busch <keith.busch@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
Reviewed-by: NGavin Shan <shan.gavin@linux.alibaba.com>

commit 65c78784135f847e49eb98e6b976e453e71100c3 upstream

This is a preparation for the next patch.

Currently, we only call release_mem_region_adjustable() in __remove_pages
if the zone is not ZONE_DEVICE, because resources that belong to HMM/devm
are being released by themselves with devm_release_mem_region.

Since we do not want to touch any zone/page stuff during the removing of
the memory (but during the offlining), we do not want to check for the
zone here.  So we need another way to tell release_mem_region_adjustable()
to not realease the resource in case it belongs to HMM/devm.

HMM/devm acquires/releases a resource through
devm_request_mem_region/devm_release_mem_region.

These resources have the flag IORESOURCE_MEM, while resources acquired by
hot-add memory path (register_memory_resource()) contain
IORESOURCE_SYSTEM_RAM.

So, we can check for this flag in release_mem_region_adjustable, and if
the resource does not contain such flag, we know that we are dealing with
a HMM/devm resource, so we can back off.

Link: http://lkml.kernel.org/r/20181127162005.15833-3-osalvador@suse.deSigned-off-by: NOscar Salvador <osalvador@suse.de>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Reviewed-by: NPavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
Reviewed-by: NGavin Shan <shan.gavin@linux.alibaba.com>

commit b69c2e20f6e4046da84ce5b33ba1ef89cb087b40 upstream

- Drop BUG_ON()s and do normal error handling instead, in
  find_next_iomem_res().

- Align function arguments on opening braces.

- Get rid of local var sibling_only in find_next_iomem_res().

- Shorten unnecessarily long first_level_children_only arg name.
Signed-off-by: NBorislav Petkov <bp@suse.de>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Brijesh Singh <brijesh.singh@amd.com>
CC: Dan Williams <dan.j.williams@intel.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Lianbo Jiang <lijiang@redhat.com>
CC: Takashi Iwai <tiwai@suse.de>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Tom Lendacky <thomas.lendacky@amd.com>
CC: Vivek Goyal <vgoyal@redhat.com>
CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
CC: bhe@redhat.com
CC: dan.j.williams@intel.com
CC: dyoung@redhat.com
CC: kexec@lists.infradead.org
CC: mingo@redhat.com
Link: <new submission>
Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
Reviewed-by: NGavin Shan <shan.gavin@linux.alibaba.com>

[ Upstream commit 49f17c26c123b60fd1c74629eef077740d16ffc2 ]

Since resources can be removed, locking should ensure that the resource
is not removed while accessing it.  However, find_next_iomem_res() does
not hold the lock while copying the data of the resource.

Keep holding the lock while the data is copied.  While at it, change the
return value to a more informative value.  It is disregarded by the
callers.

[akpm@linux-foundation.org: fix find_next_iomem_res() documentation]
Link: http://lkml.kernel.org/r/20190613045903.4922-2-namit@vmware.com
Fixes: ff3cc952 ("resource: Add remove_resource interface")
Signed-off-by: NNadav Amit <namit@vmware.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NDan Williams <dan.j.williams@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>

[ Upstream commit 010a93bf97c72f43aac664d0a685942f83d1a103 ]

Previously find_next_iomem_res() used "*res" as both an input parameter for
the range to search and the type of resource to search for, and an output
parameter for the resource we found, which makes the interface confusing.

The current callers use find_next_iomem_res() incorrectly because they
allocate a single struct resource and use it for repeated calls to
find_next_iomem_res().  When find_next_iomem_res() returns a resource, it
overwrites the start, end, flags, and desc members of the struct.  If we
call find_next_iomem_res() again, we must update or restore these fields.
The previous code restored res.start and res.end, but not res.flags or
res.desc.

Since the callers did not restore res.flags, if they searched for flags
IORESOURCE_MEM | IORESOURCE_BUSY and found a resource with flags
IORESOURCE_MEM | IORESOURCE_BUSY | IORESOURCE_SYSRAM, the next search would
incorrectly skip resources unless they were also marked as
IORESOURCE_SYSRAM.

Fix this by restructuring the interface so it takes explicit "start, end,
flags" parameters and uses "*res" only as an output parameter.

Based on a patch by Lianbo Jiang <lijiang@redhat.com>.

 [ bp: While at it:
   - make comments kernel-doc style.
   -

Originally-by: http://lore.kernel.org/lkml/20180921073211.20097-2-lijiang@redhat.comSigned-off-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Brijesh Singh <brijesh.singh@amd.com>
CC: Dan Williams <dan.j.williams@intel.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Lianbo Jiang <lijiang@redhat.com>
CC: Takashi Iwai <tiwai@suse.de>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Tom Lendacky <thomas.lendacky@amd.com>
CC: Vivek Goyal <vgoyal@redhat.com>
CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
CC: bhe@redhat.com
CC: dan.j.williams@intel.com
CC: dyoung@redhat.com
CC: kexec@lists.infradead.org
CC: mingo@redhat.com
CC: x86-ml <x86@kernel.org>
Link: http://lkml.kernel.org/r/153805812916.1157.177580438135143788.stgit@bhelgaas-glaptop.roam.corp.google.comSigned-off-by: NSasha Levin <sashal@kernel.org>

[ Upstream commit a98959fdbda1849a01b2150bb635ed559ec06700 ]

find_next_iomem_res() finds an iomem resource that covers part of a range
described by "start, end".  All callers expect that range to be inclusive,
i.e., both start and end are included, but find_next_iomem_res() doesn't
handle the end address correctly.

If it finds an iomem resource that contains exactly the end address, it
skips it, e.g., if "start, end" is [0x0-0x10000] and there happens to be an
iomem resource [mem 0x10000-0x10000] (the single byte at 0x10000), we skip
it:

  find_next_iomem_res(...)
  {
    start = 0x0;
    end = 0x10000;
    for (p = next_resource(...)) {
      # p->start = 0x10000;
      # p->end = 0x10000;
      # we *should* return this resource, but this condition is false:
      if ((p->end >= start) && (p->start < end))
        break;

Adjust find_next_iomem_res() so it allows a resource that includes the
single byte at the end of the range.  This is a corner case that we
probably don't see in practice.

Fixes: 58c1b5b0 ("[PATCH] memory hotadd fixes: find_next_system_ram catch range fix")
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Brijesh Singh <brijesh.singh@amd.com>
CC: Dan Williams <dan.j.williams@intel.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Lianbo Jiang <lijiang@redhat.com>
CC: Takashi Iwai <tiwai@suse.de>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Tom Lendacky <thomas.lendacky@amd.com>
CC: Vivek Goyal <vgoyal@redhat.com>
CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
CC: bhe@redhat.com
CC: dan.j.williams@intel.com
CC: dyoung@redhat.com
CC: kexec@lists.infradead.org
CC: mingo@redhat.com
CC: x86-ml <x86@kernel.org>
Link: http://lkml.kernel.org/r/153805812254.1157.16736368485811773752.stgit@bhelgaas-glaptop.roam.corp.google.comSigned-off-by: NSasha Levin <sashal@kernel.org>

There is currently a mismatch between the resources that will trigger
the e820_pmem driver to register/load and the resources that will
actually be surfaced as pmem ranges. register_e820_pmem() uses
walk_iomem_res_desc() which includes children and siblings. In contrast,
e820_pmem_probe() only considers top level resources. For example the
following resource tree results in the driver being loaded, but no
resources being registered:

    398000000000-39bfffffffff : PCI Bus 0000:ae
      39be00000000-39bf07ffffff : PCI Bus 0000:af
        39be00000000-39beffffffff : 0000:af:00.0
          39be10000000-39beffffffff : Persistent Memory (legacy)

Fix this up to allow definitions of "legacy" pmem ranges anywhere in
system-physical address space. Not that it is a recommended or safe to
define a pmem range in PCI space, but it is useful for debug /
experimentation, and the restriction on being a top-level resource was
arbitrary.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

And use the root resource directly from the proc private data.
Signed-off-by: NChristoph Hellwig <hch@lst.de>

We've got a bug report indicating a kernel panic at booting on an x86-32
system, and it turned out to be the invalid PCI resource assigned after
reallocation.  __find_resource() first aligns the resource start address
and resets the end address with start+size-1 accordingly, then checks
whether it's contained.  Here the end address may overflow the integer,
although resource_contains() still returns true because the function
validates only start and end address.  So this ends up with returning an
invalid resource (start > end).

There was already an attempt to cover such a problem in the commit
47ea91b4 ("Resource: fix wrong resource window calculation"), but
this case is an overseen one.

This patch adds the validity check of the newly calculated resource for
avoiding the integer overflow problem.

Bugzilla: http://bugzilla.opensuse.org/show_bug.cgi?id=1086739
Link: http://lkml.kernel.org/r/s5hpo37d5l8.wl-tiwai@suse.de
Fixes: 23c570a6 ("resource: ability to resize an allocated resource")
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Reported-by: NMichael Henders <hendersm@shaw.ca>
Tested-by: NMichael Henders <hendersm@shaw.ca>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make iomem_is_exclusive return bool due to this particular function only
using either one or zero as its return value.

No functional change.

Link: http://lkml.kernel.org/r/1513266622-15860-5-git-send-email-baiyaowei@cmss.chinamobile.comSigned-off-by: NYaowei Bai <baiyaowei@cmss.chinamobile.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Set resource structs inserted by __reserve_region_with_split() to have the
correct type.  Setting the type doesn't fix any functional problem but
makes %pR on the resource work better.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

When we reserve regions because the user specified a "reserve=" parameter,
set the resource type to either IORESOURCE_IO (for regions below 0x10000)
or IORESOURCE_MEM.  The test for 0x10000 is just a heuristic; obviously
there can be memory below 0x10000 as well.

Improve documentation of the "reserve=" parameter.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

In order for memory pages to be properly mapped when SEV is active, it's
necessary to use the PAGE_KERNEL protection attribute as the base
protection.  This ensures that memory mapping of, e.g. ACPI tables,
receives the proper mapping attributes.
Signed-off-by: NTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Tested-by: NBorislav Petkov <bp@suse.de>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: kvm@vger.kernel.org
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Link: https://lkml.kernel.org/r/20171020143059.3291-11-brijesh.singh@amd.com

In preperation for a new function that will need additional resource
information during the resource walk, update the resource walk callback to
pass the resource structure.  Since the current callback start and end
arguments are pulled from the resource structure, the callback functions
can obtain them from the resource structure directly.
Signed-off-by: NTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Tested-by: NBorislav Petkov <bp@suse.de>
Cc: kvm@vger.kernel.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lkml.kernel.org/r/20171020143059.3291-10-brijesh.singh@amd.com

The walk_iomem_res_desc(), walk_system_ram_res() and walk_system_ram_range()
functions each have much of the same code.

Create a new function that consolidates the common code from these
functions in one place to reduce the amount of duplicated code.
Signed-off-by: NTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Tested-by: NBorislav Petkov <bp@suse.de>
Cc: kvm@vger.kernel.org
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/20171020143059.3291-9-brijesh.singh@amd.com

In commit c4004b02 ("x86: remove the kernel code/data/bss resources
from /proc/iomem") I was hoping to remove the phyiscal kernel address
data from /proc/iomem entirely, but that had to be reverted because some
system programs actually use it.

This limits all the detailed resource information to properly
credentialed users instead.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

insert_resource() and remove_resouce() are called by producers
of resources, such as FW modules and bus drivers.  These modules
may be implemented as loadable modules.

Export insert_resource() and remove_resouce() so that they can
be called from such modules.

link: https://lkml.org/lkml/2016/3/8/872Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

insert_resource() and insert_resource_conflict() are called
by resource producers to insert a new resource.  When there
is any conflict, they move conflicting resources down to the
children of the new resource.  There is no destructor of these
interfaces, however.

Add remove_resource(), which removes a resource previously
inserted by insert_resource() or insert_resource_conflict(),
and moves the children up to where they were before.

__release_resource() is changed to have @release_child, so
that this function can be used for remove_resource() as well.

Also add comments to clarify that these functions are intended
for producers of resources to avoid any confusion with
request/release_resource() for consumers.
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

__request_region() sets 'flags' of a new resource from @parent
as it inherits the parent's attribute.  When a target resource
has a conflict, this function inserts the new resource entry
under the conflicted entry by updating @parent.  In this case,
the new resource entry needs to inherit attribute from the updated
parent.  This conflict is a typical case since __request_region()
is used to allocate a new resource from a specific resource range.

For instance, request_mem_region() calls __request_region() with
@parent set to &iomem_resource, which is the root entry of the
whole iomem range.  When this request results in inserting a new
entry "DEV-A" under "BUS-1", "DEV-A" needs to inherit from the
immediate parent "BUS-1" as it holds specific attribute for the
range.

root (&iomem_resource)
 :
 + "BUS-1"
    + "DEV-A"

Change __request_region() to set 'flags' and 'desc' of a new entry
from the immediate parent.
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

In __request_region, if a conflict with a BUSY and MUXED resource is
detected, then the caller goes to sleep and waits for the resource to be
released.  A pointer on the conflicting resource is kept.  At wake-up
this pointer is used as a parent to retry to request the region.

A first problem is that this pointer might well be invalid (if for
example the conflicting resource have already been freed).  Another
problem is that the next call to __request_region() fails to detect a
remaining conflict.  The previously conflicting resource is passed as a
parameter and __request_region() will look for a conflict among the
children of this resource and not at the resource itself.  It is likely
to succeed anyway, even if there is still a conflict.

Instead, the parent of the conflicting resource should be passed to
__request_region().

As a fix, this patch doesn't update the parent resource pointer in the
case we have to wait for a muxed region right after.
Reported-and-tested-by: NVincent Pelletier <plr.vincent@gmail.com>
Signed-off-by: NSimon Guinot <simon.guinot@sequanux.org>
Tested-by: NVincent Donnefort <vdonnefort@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

walk_iomem_res_desc() replaced walk_iomem_res() and there is no
caller to walk_iomem_res() any more. Kill it. Also remove @name
from find_next_iomem_res() as it is no longer used.
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NDave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Jakub Sitnicki <jsitnicki@gmail.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm <linux-mm@kvack.org>
Link: http://lkml.kernel.org/r/1453841853-11383-17-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

Add a new interface, walk_iomem_res_desc(), which walks through
the iomem table by identifying a target with @flags and @desc.
This interface provides the same functionality as
walk_iomem_res(), but does not use strcmp() to @name for better
efficiency.

walk_iomem_res() is deprecated and will be removed in a later
patch.
Requested-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
[ Fixup comments. ]
Signed-off-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Jakub Sitnicki <jsitnicki@gmail.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm <linux-mm@kvack.org>
Link: http://lkml.kernel.org/r/1453841853-11383-14-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

Change region_intersects() to identify a target with @flags and
@desc, instead of @name with strcmp().

Change the callers of region_intersects(), memremap() and
devm_memremap(), to set IORESOURCE_SYSTEM_RAM in @flags and
IORES_DESC_NONE in @desc when searching System RAM.

Also, export region_intersects() so that the ACPI EINJ error
injection driver can call this function in a later patch.
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NDan Williams <dan.j.williams@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jakub Sitnicki <jsitnicki@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm <linux-mm@kvack.org>
Link: http://lkml.kernel.org/r/1453841853-11383-13-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

Now that all System RAM resource entries have been initialized
to IORESOURCE_SYSTEM_RAM type, change walk_system_ram_res() and
walk_system_ram_range() to call find_next_iomem_res() by setting
@res.flags to IORESOURCE_SYSTEM_RAM and @name to NULL. With this
change, they walk through the iomem table to find System RAM
ranges without the need to do strcmp() on the resource names.

No functional change is made to the interfaces.
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
[ Boris: fixup comments. ]
Signed-off-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jakub Sitnicki <jsitnicki@gmail.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm <linux-mm@kvack.org>
Link: http://lkml.kernel.org/r/1453841853-11383-11-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

walk_iomem_res() and region_intersects() still need to use
strcmp() for searching a resource entry by @name in the iomem
table.

This patch introduces I/O resource descriptor 'desc' in struct
resource for the iomem search interfaces. Drivers can assign
their unique descriptor to a range when they support the search
interfaces.

Otherwise, 'desc' is set to IORES_DESC_NONE (0). This avoids
changing most of the drivers as they typically allocate resource
entries statically, or by calling alloc_resource(), kzalloc(),
or alloc_bootmem_low(), which set the field to zero by default.
A later patch will address some drivers that use kmalloc()
without zero'ing the field.

Also change release_mem_region_adjustable() to set 'desc' when
its resource entry gets separated. Other resource interfaces are
also changed to initialize 'desc' explicitly although
alloc_resource() sets it to 0.
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jakub Sitnicki <jsitnicki@gmail.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm <linux-mm@kvack.org>
Link: http://lkml.kernel.org/r/1453841853-11383-4-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

I/O resource flags consist of I/O resource types and modifier
bits. Therefore, checking an I/O resource type in 'flags' must
be performed with a bitwise operation.

Fix find_next_iomem_res() and region_intersects() that simply
compare 'flags' against a given value.

Also change __request_region() to set 'res->flags' from
resource_type() and resource_ext_type() of the parent, so that
children nodes will inherit the extended I/O resource type.
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jakub Sitnicki <jsitnicki@gmail.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm <linux-mm@kvack.org>
Link: http://lkml.kernel.org/r/1453841853-11383-3-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

This effectively promotes IORESOURCE_BUSY to IORESOURCE_EXCLUSIVE
semantics by default.  If userspace really believes it is safe to access
the memory region it can also perform the extra step of disabling an
active driver.  This protects device address ranges with read side
effects and otherwise directs userspace to use the driver.

Persistent memory presents a large "mistake surface" to /dev/mem as now
accidental writes can corrupt a filesystem.

In general if a device driver is busily using a memory region it already
informs other parts of the kernel to not touch it via
request_mem_region().  /dev/mem should honor the same safety restriction
by default.  Debugging a device driver from userspace becomes more
difficult with this enabled.  Any application using /dev/mem or mmap of
sysfs pci resources will now need to perform the extra step of either:

1/ Disabling the driver, for example:

   echo <device id> > /dev/bus/<parent bus>/drivers/<driver name>/unbind

2/ Rebooting with "iomem=relaxed" on the command line

3/ Recompiling with CONFIG_IO_STRICT_DEVMEM=n

Traditional users of /dev/mem like dosemu are unaffected because the
first 1MB of memory is not subject to the IO_STRICT_DEVMEM restriction.
Legacy X configurations use /dev/mem to talk to graphics hardware, but
that functionality has since moved to kernel graphics drivers.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NKees Cook <keescook@chromium.org>
Acked-by: NIngo Molnar <mingo@redhat.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

region_is_ram() is used to prevent the establishment of aliased mappings
to physical "System RAM" with incompatible cache settings.  However, it
uses "-1" to indicate both "unknown" memory ranges (ranges not described
by platform firmware) and "mixed" ranges (where the parameters describe
a range that partially overlaps "System RAM").

Fix this up by explicitly tracking the "unknown" vs "mixed" resource
cases and returning REGION_INTERSECTS, REGION_MIXED, or REGION_DISJOINT.
This re-write also adds support for detecting when the requested region
completely eclipses all of a resource.  Note, the implementation treats
overlaps between "unknown" and the requested memory type as
REGION_INTERSECTS.

Finally, other memory types can be passed in by name, for now the only
usage "System RAM".
Suggested-by: NLuis R. Rodriguez <mcgrof@suse.com>
Reviewed-by: NToshi Kani <toshi.kani@hp.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

region_is_ram() looks up the iomem_resource table to check if
a target range is in RAM.  However, it always returns with -1
due to invalid range checks. It always breaks the loop at the
first entry of the table.

Another issue is that it compares p->flags and flags, but it always
fails. flags is declared as int, which makes it as a negative value
with IORESOURCE_BUSY (0x80000000) set while p->flags is unsigned long.

Fix the range check and flags so that region_is_ram() works as
advertised.
Signed-off-by: NToshi Kani <toshi.kani@hp.com>
Reviewed-by: NDan Williams <dan.j.williams@intel.com>
Cc: Mike Travis <travis@sgi.com>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Roland Dreier <roland@purestorage.com>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1437088996-28511-4-git-send-email-toshi.kani@hp.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

All users of __check_region(), check_region(), and check_mem_region() are
gone.  We got rid of the last user in v4.0-rc1.  Remove them.

bloat-o-meter on x86_64 shows:

add/remove: 0/3 grow/shrink: 0/0 up/down: 0/-102 (-102)
function                                     old     new   delta
__kstrtab___check_region                      15       -     -15
__ksymtab___check_region                      16       -     -16
__check_region                                71       -     -71
Signed-off-by: NJakub Sitnicki <jsitnicki@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently ACPI, PCI and pnp all implement the same resource list
management with different data structure. We need to transfer from
one data structure into another when passing resources from one
subsystem into another subsystem. So move struct resource_list_entry
from ACPI into resource core and rename it as resource_entry,
then it could be reused by different subystems and avoid the data
structure conversion.

Introduce dedicated header file resource_ext.h instead of embedding
it into ioport.h to avoid header file inclusion order issues.
Signed-off-by: NJiang Liu <jiang.liu@linux.intel.com>
Acked-by: NVinod Koul <vinod.koul@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We have a large university system in the UK that is experiencing very long
delays modprobing the driver for a specific I/O device.  The delay is from
8-10 minutes per device and there are 31 devices in the system.  This 4 to
5 hour delay in starting up those I/O devices is very much a burden on the
customer.

There are two causes for requiring a restart/reload of the drivers.  First
is periodic preventive maintenance (PM) and the second is if any of the
devices experience a fatal error.  Both of these trigger this excessively
long delay in bringing the system back up to full capability.

The problem was tracked down to a very slow IOREMAP operation and the
excessively long ioresource lookup to insure that the user is not
attempting to ioremap RAM.  These patches provide a speed up to that
function.

The modprobe time appears to be affected quite a bit by previous activity
on the ioresource list, which I suspect is due to cache preloading.  While
the overall improvement is impacted by other overhead of starting the
devices, this drastically improves the modprobe time.

Also our system is considerably smaller so the percentages gained will not
be the same.  Best case improvement with the modprobe on our 20 device
smallish system was from 'real 5m51.913s' to 'real 0m18.275s'.

This patch (of 2):

Since the ioremap operation is verifying that the specified address range
is NOT RAM, it will search the entire ioresource list if the condition is
true.  To make matters worse, it does this one 4k page at a time.  For a
128M BAR region this is 32 passes to determine the entire region does not
contain any RAM addresses.

This patch provides another resource lookup function, region_is_ram, that
searches for the entire region specified, verifying that it is completely
contained within the resource region.  If it is found, then it is checked
to be RAM or not, within a single pass.

The return result reflects if it was found or not (-1), and whether it is
RAM (1) or not (0).  This allows the caller to fallback to the previous
page by page search if it was not found.

[akpm@linux-foundation.org: fix spellos and typos in comment]
Signed-off-by: NMike Travis <travis@sgi.com>
Acked-by: NAlex Thorlton <athorlton@sgi.com>
Reviewed-by: NCliff Wickman <cpw@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Provide device-managed implementations of the request_resource() and
release_resource() functions.  Upon failure to request a resource, the new
devm_request_resource() function will output an error message for
consistent error reporting.
Signed-off-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NTejun Heo <tj@kernel.org>

Richard and Daniel reported that UML is broken due to changes to
resource traversal functions.  Problem is that iomem_resource.child can
be null and new code does not consider that possibility.  Old code used
a for loop and that loop will not even execute if p was null.

Revert back to for() loop logic and bail out if p is null.

I also moved sibling_only check out of resource_lock. There is no
reason to keep it inside the lock.

Following is backtrace of the UML crash.

RIP: 0033:[<0000000060039b9f>]
RSP: 0000000081459da0  EFLAGS: 00010202
RAX: 0000000000000000 RBX: 00000000219b3fff RCX: 000000006010d1d9
RDX: 0000000000000001 RSI: 00000000602dfb94 RDI: 0000000081459df8
RBP: 0000000081459de0 R08: 00000000601b59f4 R09: ffffffff0000ff00
R10: ffffffff0000ff00 R11: 0000000081459e88 R12: 0000000081459df8
R13: 00000000219b3fff R14: 00000000602dfb94 R15: 0000000000000000
Kernel panic - not syncing: Segfault with no mm
CPU: 0 PID: 1 Comm: swapper Not tainted 3.16.0-10454-g58d08e3b #13
Stack:
 00000000 000080d0 81459df0 219b3fff
 81459e70 6010d1d9 ffffffff 6033e010
 81459e50 6003a269 81459e30 00000000
Call Trace:
 [<6010d1d9>] ? kclist_add_private+0x0/0xe7
 [<6003a269>] walk_system_ram_range+0x61/0xb7
 [<6000e859>] ? proc_kcore_init+0x0/0xf1
 [<6010d574>] kcore_update_ram+0x4c/0x168
 [<6010d72e>] ? kclist_add+0x0/0x2e
 [<6000e943>] proc_kcore_init+0xea/0xf1
 [<6000e859>] ? proc_kcore_init+0x0/0xf1
 [<6000e859>] ? proc_kcore_init+0x0/0xf1
 [<600189f0>] do_one_initcall+0x13c/0x204
 [<6004ca46>] ? parse_args+0x1df/0x2e0
 [<6004c82d>] ? parameq+0x0/0x3a
 [<601b5990>] ? strcpy+0x0/0x18
 [<60001e1a>] kernel_init_freeable+0x240/0x31e
 [<6026f1c0>] kernel_init+0x12/0x148
 [<60019fad>] new_thread_handler+0x81/0xa3

Fixes 8c86e70a ("resource: provide new functions to walk
through resources").
Reported-by: NDaniel Walter <sahne@0x90.at>
Tested-by: NRichard Weinberger <richard@nod.at>
Tested-by: NToralf Förster <toralf.foerster@gmx.de>
Tested-by: NDaniel Walter <sahne@0x90.at>
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I have added two more functions to walk through resources.

Currently walk_system_ram_range() deals with pfn and /proc/iomem can
contain partial pages.  By dealing in pfn, callback function loses the
info that last page of a memory range is a partial page and not the full
page.  So I implemented walk_system_ram_res() which returns u64 values to
callback functions and now it properly return start and end address.

walk_system_ram_range() uses find_next_system_ram() to find the next ram
resource.  This in turn only travels through siblings of top level child
and does not travers through all the nodes of the resoruce tree.  I also
need another function where I can walk through all the resources, for
example figure out where "GART" aperture is.  Figure out where ACPI memory
is.

So I wrote another function walk_iomem_res() which walks through all
/proc/iomem resources and returns matches as asked by caller.  Caller can
specify "name" of resource, start and end and flags.

Got rid of find_next_system_ram_res() and instead implemented more generic
find_next_iomem_res() which can be used to traverse top level children
only based on an argument.
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The resource map sanity check message is a bit confusing.  Change it to be
more readable:

  -resource map sanity check conflict: 0xfed10000 0xfed15fff 0xfed10000 0xfed13fff pnp 00:01
  +resource sanity check: requesting [mem 0xfed10000-0xfed15fff], which spans more than pnp 00:01 [mem 0xfed10000-0xfed13fff]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

sparse says:

kernel/resource.c:518:5: warning:
 symbol 'reallocate_resource' was not declared. Should it be static?
Signed-off-by: NDaeseok Youn <daeseok.youn@gmail.com>
Reviewed-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>