linux.git/include/linux/alloc_tag.h, branch v6.12.80

alloc_tag: fix set_codetag_empty() when !CONFIG_MEM_ALLOC_PROFILING_DEBUG

2024-12-27T13:02:13+00:00

commit 60da7445a142bd15e67f3cda915497781c3f781f upstream.

It was recently noticed that set_codetag_empty() might be used not only to
mark NULL alloctag references as empty to avoid warnings but also to reset
valid tags (in clear_page_tag_ref()).  Since set_codetag_empty() is
defined as NOOP for CONFIG_MEM_ALLOC_PROFILING_DEBUG=n, such use of
set_codetag_empty() leads to subtle bugs.  Fix set_codetag_empty() for
CONFIG_MEM_ALLOC_PROFILING_DEBUG=n to reset the tag reference.

Link: https://lkml.kernel.org/r/20241130001423.1114965-2-surenb@google.com
Fixes: a8fc28dad6d5 ("alloc_tag: introduce clear_page_tag_ref() helper function")
Signed-off-by: Suren Baghdasaryan 
Reported-by: David Wang <00107082@163.com>
Closes: https://lore.kernel.org/lkml/20241124074318.399027-1-00107082@163.com/
Cc: David Wang <00107082@163.com>
Cc: Kent Overstreet 
Cc: Mike Rapoport (Microsoft) 
Cc: Pasha Tatashin 
Cc: Sourav Panda 
Cc: Yu Zhao 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

mm/codetag: fix null pointer check logic for ref and tag

2024-10-31T03:14:10+00:00

When we compile and load lib/slub_kunit.c,it will cause a panic.

The root cause is that __kmalloc_cache_noprof was directly called instead
of kmem_cache_alloc,which resulted in no alloc_tag being allocated.This
caused current->alloc_tag to be null,leading to a null pointer dereference
in alloc_tag_ref_set.

Despite the fact that my colleague Pei Xiao will later fix the code in
slub_kunit.c,we still need fix null pointer check logic for ref and tag to
avoid panic caused by a null pointer dereference.

Here is the log for the panic:

[   74.779373][ T2158] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
[   74.780130][ T2158] Mem abort info:
[   74.780406][ T2158]   ESR = 0x0000000096000004
[   74.780756][ T2158]   EC = 0x25: DABT (current EL), IL = 32 bits
[   74.781225][ T2158]   SET = 0, FnV = 0
[   74.781529][ T2158]   EA = 0, S1PTW = 0
[   74.781836][ T2158]   FSC = 0x04: level 0 translation fault
[   74.782288][ T2158] Data abort info:
[   74.782577][ T2158]   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
[   74.783068][ T2158]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[   74.783533][ T2158]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[   74.784010][ T2158] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000105f34000
[   74.784586][ T2158] [0000000000000020] pgd=0000000000000000, p4d=0000000000000000
[   74.785293][ T2158] Internal error: Oops: 0000000096000004 [#1] SMP
[   74.785805][ T2158] Modules linked in: slub_kunit kunit ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_mangle 4
[   74.790661][ T2158] CPU: 0 UID: 0 PID: 2158 Comm: kunit_try_catch Kdump: loaded Tainted: G        W        N 6.12.0-rc3+ #2
[   74.791535][ T2158] Tainted: [W]=WARN, [N]=TEST
[   74.791889][ T2158] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
[   74.792479][ T2158] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   74.793101][ T2158] pc : alloc_tagging_slab_alloc_hook+0x120/0x270
[   74.793607][ T2158] lr : alloc_tagging_slab_alloc_hook+0x120/0x270
[   74.794095][ T2158] sp : ffff800084d33cd0
[   74.794418][ T2158] x29: ffff800084d33cd0 x28: 0000000000000000 x27: 0000000000000000
[   74.795095][ T2158] x26: 0000000000000000 x25: 0000000000000012 x24: ffff80007b30e314
[   74.795822][ T2158] x23: ffff000390ff6f10 x22: 0000000000000000 x21: 0000000000000088
[   74.796555][ T2158] x20: ffff000390285840 x19: fffffd7fc3ef7830 x18: ffffffffffffffff
[   74.797283][ T2158] x17: ffff8000800e63b4 x16: ffff80007b33afc4 x15: ffff800081654c00
[   74.798011][ T2158] x14: 0000000000000000 x13: 205d383531325420 x12: 5b5d383734363537
[   74.798744][ T2158] x11: ffff800084d337e0 x10: 000000000000005d x9 : 00000000ffffffd0
[   74.799476][ T2158] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008219d188 x6 : c0000000ffff7fff
[   74.800206][ T2158] x5 : ffff0003fdbc9208 x4 : ffff800081edd188 x3 : 0000000000000001
[   74.800932][ T2158] x2 : 0beaa6dee1ac5a00 x1 : 0beaa6dee1ac5a00 x0 : ffff80037c2cb000
[   74.801656][ T2158] Call trace:
[   74.801954][ T2158]  alloc_tagging_slab_alloc_hook+0x120/0x270
[   74.802494][ T2158]  __kmalloc_cache_noprof+0x148/0x33c
[   74.802976][ T2158]  test_kmalloc_redzone_access+0x4c/0x104 [slub_kunit]
[   74.803607][ T2158]  kunit_try_run_case+0x70/0x17c [kunit]
[   74.804124][ T2158]  kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit]
[   74.804768][ T2158]  kthread+0x10c/0x118
[   74.805141][ T2158]  ret_from_fork+0x10/0x20
[   74.805540][ T2158] Code: b9400a80 11000400 b9000a80 97ffd858 (f94012d3)
[   74.806176][ T2158] SMP: stopping secondary CPUs
[   74.808130][ T2158] Starting crashdump kernel...

Link: https://lkml.kernel.org/r/20241020070819.307944-1-hao.ge@linux.dev
Fixes: e0a955bf7f61 ("mm/codetag: add pgalloc_tag_copy()")
Signed-off-by: Hao Ge 
Acked-by: Suren Baghdasaryan 
Suggested-by: Suren Baghdasaryan 
Acked-by: Yu Zhao 
Cc: Kent Overstreet 
Signed-off-by: Andrew Morton

mm/codetag: add pgalloc_tag_copy()

2024-09-09T23:39:18+00:00

Add pgalloc_tag_copy() to transfer the codetag from the old folio to the
new one during migration.  This makes original allocation sites persist
cross migration rather than lump into the get_new_folio callbacks passed
into migrate_pages(), e.g., compaction_alloc():

  # echo 1 >/proc/sys/vm/compact_memory
  # grep compaction_alloc /proc/allocinfo

Before this patch:
  132968448  32463  mm/compaction.c:1880 func:compaction_alloc

After this patch:
          0      0  mm/compaction.c:1880 func:compaction_alloc

Link: https://lkml.kernel.org/r/20240906042108.1150526-3-yuzhao@google.com
Fixes: dcfe378c81f7 ("lib: introduce support for page allocation tagging")
Signed-off-by: Yu Zhao 
Acked-by: Suren Baghdasaryan 
Cc: Kent Overstreet 
Cc: Muchun Song 
Cc: 
Signed-off-by: Andrew Morton

mm/codetag: fix a typo

2024-09-09T23:39:18+00:00

Link: https://lkml.kernel.org/r/20240906042108.1150526-1-yuzhao@google.com
Fixes: 22d407b164ff ("lib: add allocation tagging support for memory allocation profiling")
Signed-off-by: Yu Zhao 
Acked-by: Suren Baghdasaryan 
Acked-by: Muchun Song 
Cc: Kent Overstreet 
Signed-off-by: Andrew Morton

lib: add missing newline character in the warning message

2024-07-18T04:05:18+00:00

Link: https://lkml.kernel.org/r/20240711220457.1751071-1-surenb@google.com
Fixes: 22d407b164ff ("lib: add allocation tagging support for memory allocation profiling")
Signed-off-by: Suren Baghdasaryan 
Cc: Kees Cook 
Cc: Kent Overstreet 
Cc: Pasha Tatashin 
Cc: Sourav Panda 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton

mm: percpu: Include smp.h in alloc_tag.h

2024-05-26T21:40:39+00:00

percpu.h depends on smp.h, but doesn't include it directly because of
circular header dependency issues; percpu.h is needed in a bunch of low
level headers.

This fixes a randconfig build error on mips:

  include/linux/alloc_tag.h: In function '__alloc_tag_ref_set':
  include/asm-generic/percpu.h:31:40: error: implicit declaration of function 'raw_smp_processor_id' [-Werror=implicit-function-declaration]

Reported-by: kernel test robot 
Fixes: 24e44cc22aa3 ("mm: percpu: enable per-cpu allocation tagging")
Closes: https://lore.kernel.org/oe-kbuild-all/202405210052.DIrMXJNz-lkp@intel.com/
Signed-off-by: Kent Overstreet 
Signed-off-by: Linus Torvalds

codetag: debug: mark codetags for reserved pages as empty

2024-04-26T03:55:58+00:00

To avoid debug warnings while freeing reserved pages which were not
allocated with usual allocators, mark their codetags as empty before
freeing.

Link: https://lkml.kernel.org/r/20240321163705.3067592-35-surenb@google.com
Signed-off-by: Suren Baghdasaryan 
Reviewed-by: Kees Cook 
Tested-by: Kees Cook 
Cc: Alexander Viro 
Cc: Alex Gaynor 
Cc: Alice Ryhl 
Cc: Andreas Hindborg 
Cc: Benno Lossin 
Cc: "Björn Roy Baron" 
Cc: Boqun Feng 
Cc: Christoph Lameter 
Cc: Dennis Zhou 
Cc: Gary Guo 
Cc: Kent Overstreet 
Cc: Miguel Ojeda 
Cc: Pasha Tatashin 
Cc: Peter Zijlstra 
Cc: Tejun Heo 
Cc: Vlastimil Babka 
Cc: Wedson Almeida Filho 
Signed-off-by: Andrew Morton

codetag: debug: skip objext checking when it's for objext itself

2024-04-26T03:55:57+00:00

objext objects are created with __GFP_NO_OBJ_EXT flag and therefore have
no corresponding objext themselves (otherwise we would get an infinite
recursion). When freeing these objects their codetag will be empty and
when CONFIG_MEM_ALLOC_PROFILING_DEBUG is enabled this will lead to false
warnings. Introduce CODETAG_EMPTY special codetag value to mark
allocations which intentionally lack codetag to avoid these warnings.
Set objext codetags to CODETAG_EMPTY before freeing to indicate that
the codetag is expected to be empty.

Link: https://lkml.kernel.org/r/20240321163705.3067592-34-surenb@google.com
Signed-off-by: Suren Baghdasaryan 
Tested-by: Kees Cook 
Cc: Alexander Viro 
Cc: Alex Gaynor 
Cc: Alice Ryhl 
Cc: Andreas Hindborg 
Cc: Benno Lossin 
Cc: "Björn Roy Baron" 
Cc: Boqun Feng 
Cc: Christoph Lameter 
Cc: Dennis Zhou 
Cc: Gary Guo 
Cc: Kent Overstreet 
Cc: Miguel Ojeda 
Cc: Pasha Tatashin 
Cc: Peter Zijlstra 
Cc: Tejun Heo 
Cc: Vlastimil Babka 
Cc: Wedson Almeida Filho 
Signed-off-by: Andrew Morton

lib: add memory allocations report in show_mem()

2024-04-26T03:55:57+00:00

Include allocations in show_mem reports.

Link: https://lkml.kernel.org/r/20240321163705.3067592-33-surenb@google.com
Signed-off-by: Kent Overstreet 
Signed-off-by: Suren Baghdasaryan 
Reviewed-by: Vlastimil Babka 
Tested-by: Kees Cook 
Cc: Alexander Viro 
Cc: Alex Gaynor 
Cc: Alice Ryhl 
Cc: Andreas Hindborg 
Cc: Benno Lossin 
Cc: "Björn Roy Baron" 
Cc: Boqun Feng 
Cc: Christoph Lameter 
Cc: Dennis Zhou 
Cc: Gary Guo 
Cc: Miguel Ojeda 
Cc: Pasha Tatashin 
Cc: Peter Zijlstra 
Cc: Tejun Heo 
Cc: Wedson Almeida Filho 
Signed-off-by: Andrew Morton

rhashtable: plumb through alloc tag

2024-04-26T03:55:57+00:00

This gives better memory allocation profiling results; rhashtable
allocations will be accounted to the code that initialized the rhashtable.

[surenb@google.com: undo _noprof additions in the documentation]
  Link: https://lkml.kernel.org/r/20240326231453.1206227-1-surenb@google.com
Link: https://lkml.kernel.org/r/20240321163705.3067592-32-surenb@google.com
Signed-off-by: Kent Overstreet 
Signed-off-by: Suren Baghdasaryan 
Tested-by: Kees Cook 
Cc: Alexander Viro 
Cc: Alex Gaynor 
Cc: Alice Ryhl 
Cc: Andreas Hindborg 
Cc: Benno Lossin 
Cc: "Björn Roy Baron" 
Cc: Boqun Feng 
Cc: Christoph Lameter 
Cc: Dennis Zhou 
Cc: Gary Guo 
Cc: Miguel Ojeda 
Cc: Pasha Tatashin 
Cc: Peter Zijlstra 
Cc: Tejun Heo 
Cc: Vlastimil Babka 
Cc: Wedson Almeida Filho 
Signed-off-by: Andrew Morton