| Age | Commit message (Collapse) | Author | Files | Lines |
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Batched completions can clear multiple bits, but we're only decrementing
the wait_cnt by one each time. This can cause waiters to never be woken,
stalling IO. Use the batched count instead.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215679
Signed-off-by: Keith Busch <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.
Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Wolfram Sang <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
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Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
llist_add_batch and llist_del_first. x86 CMPXCHG instruction returns
success in ZF flag, so this change saves a compare after cmpxchg.
Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg
fails, enabling further code simplifications.
No functional change intended.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Uros Bizjak <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
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An argument list like "arg=val arg2 \"" can trigger a page fault if the
page pointed by 'args[0xffffffff]' is not mapped and potential memory
corruption otherwise (unlikely but possible if the bogus address is mapped
and contents happen to match the ascii value of the quote character).
The fix is to ensure that we load 'args[i-1]' only when (i > 0).
Prior to this commit the following command would trigger an
unhandled page fault in the kernel:
root@(none):/linus/fs/fat# insmod ./fat.ko "foo=bar \""
[ 33.870507] BUG: unable to handle page fault for address: ffff888204252608
[ 33.872180] #PF: supervisor read access in kernel mode
[ 33.873414] #PF: error_code(0x0000) - not-present page
[ 33.874650] PGD 4401067 P4D 4401067 PUD 0
[ 33.875321] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
[ 33.876113] CPU: 16 PID: 399 Comm: insmod Not tainted 5.19.0-dbg-DEV #4
[ 33.877193] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-4 04/01/2014
[ 33.878739] RIP: 0010:next_arg+0xd1/0x110
[ 33.879399] Code: 22 75 1d 41 c6 04 01 00 41 80 f8 22 74 18 eb 35 4c 89 0e 45 31 d2 4c 89 cf 48 c7 02 00 00 00 00 41 80 f8 22 75 1f 41 8d 42 ff <41> 80 3c 01 22 75 14 41 c6 04 01 00 eb 0d 48 c7 02 00 00 00 00 41
[ 33.882338] RSP: 0018:ffffc90001253d08 EFLAGS: 00010246
[ 33.883174] RAX: 00000000ffffffff RBX: ffff888104252608 RCX: 0fc317bba1c1dd00
[ 33.884311] RDX: ffffc90001253d40 RSI: ffffc90001253d48 RDI: ffff888104252609
[ 33.885450] RBP: ffffc90001253d10 R08: 0000000000000022 R09: ffff888104252609
[ 33.886595] R10: 0000000000000000 R11: ffffffff82c7ff20 R12: 0000000000000282
[ 33.887748] R13: 00000000ffff8000 R14: 0000000000000000 R15: 0000000000007fff
[ 33.888887] FS: 00007f04ec7432c0(0000) GS:ffff88813d300000(0000) knlGS:0000000000000000
[ 33.890183] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 33.891111] CR2: ffff888204252608 CR3: 0000000100f36005 CR4: 0000000000170ee0
[ 33.892241] Call Trace:
[ 33.892641] <TASK>
[ 33.892989] parse_args+0x8f/0x220
[ 33.893538] load_module+0x138b/0x15a0
[ 33.894149] ? prepare_coming_module+0x50/0x50
[ 33.894879] ? kernel_read_file_from_fd+0x5f/0x90
[ 33.895639] __se_sys_finit_module+0xce/0x130
[ 33.896342] __x64_sys_finit_module+0x1d/0x20
[ 33.897042] do_syscall_64+0x44/0xa0
[ 33.897622] entry_SYSCALL_64_after_hwframe+0x63/0xcd
[ 33.898434] RIP: 0033:0x7f04ec85ef79
[ 33.899009] Code: 48 8d 3d da db 0d 00 0f 05 eb a5 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d c7 9e 0d 00 f7 d8 64 89 01 48
[ 33.901912] RSP: 002b:00007fffae81bfe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[ 33.903081] RAX: ffffffffffffffda RBX: 0000559c5f1d2640 RCX: 00007f04ec85ef79
[ 33.904191] RDX: 0000000000000000 RSI: 0000559c5f1d12a0 RDI: 0000000000000003
[ 33.905304] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[ 33.906421] R10: 0000000000000003 R11: 0000000000000246 R12: 0000559c5f1d12a0
[ 33.907526] R13: 0000000000000000 R14: 0000559c5f1d25f0 R15: 0000559c5f1d12a0
[ 33.908631] </TASK>
[ 33.908986] Modules linked in: fat(+) [last unloaded: fat]
[ 33.909843] CR2: ffff888204252608
[ 33.910375] ---[ end trace 0000000000000000 ]---
[ 33.911172] RIP: 0010:next_arg+0xd1/0x110
[ 33.911796] Code: 22 75 1d 41 c6 04 01 00 41 80 f8 22 74 18 eb 35 4c 89 0e 45 31 d2 4c 89 cf 48 c7 02 00 00 00 00 41 80 f8 22 75 1f 41 8d 42 ff <41> 80 3c 01 22 75 14 41 c6 04 01 00 eb 0d 48 c7 02 00 00 00 00 41
[ 33.914643] RSP: 0018:ffffc90001253d08 EFLAGS: 00010246
[ 33.915446] RAX: 00000000ffffffff RBX: ffff888104252608 RCX: 0fc317bba1c1dd00
[ 33.916544] RDX: ffffc90001253d40 RSI: ffffc90001253d48 RDI: ffff888104252609
[ 33.917636] RBP: ffffc90001253d10 R08: 0000000000000022 R09: ffff888104252609
[ 33.918727] R10: 0000000000000000 R11: ffffffff82c7ff20 R12: 0000000000000282
[ 33.919821] R13: 00000000ffff8000 R14: 0000000000000000 R15: 0000000000007fff
[ 33.920908] FS: 00007f04ec7432c0(0000) GS:ffff88813d300000(0000) knlGS:0000000000000000
[ 33.922125] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 33.923017] CR2: ffff888204252608 CR3: 0000000100f36005 CR4: 0000000000170ee0
[ 33.924098] Kernel panic - not syncing: Fatal exception
[ 33.925776] Kernel Offset: disabled
[ 33.926347] Rebooting in 10 seconds..
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Neel Natu <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
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Use atomic_long_try_cmpxchg instead of
atomic_long_cmpxchg (*ptr, old, new) == old in __sbitmap_queue_get_batch.
x86 CMPXCHG instruction returns success in ZF flag, so this change
saves a compare after cmpxchg (and related move instruction in front
of cmpxchg).
Also, atomic_long_cmpxchg implicitly assigns old *ptr value to "old"
when cmpxchg fails, enabling further code simplifications, e.g.
an extra memory read can be avoided in the loop.
No functional change intended.
Cc: Jens Axboe <[email protected]>
Signed-off-by: Uros Bizjak <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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When __sbq_wake_up() decrements wait_cnt to 0 but races with someone
else waking the waiter on the waitqueue (so the waitqueue becomes
empty), it exits without reseting wait_cnt to wake_batch number. Once
wait_cnt is 0, nobody will ever reset the wait_cnt or wake the new
waiters resulting in possible deadlocks or busyloops. Fix the problem by
making sure we reset wait_cnt even if we didn't wake up anybody in the
end.
Fixes: 040b83fcecfb ("sbitmap: fix possible io hung due to lost wakeup")
Reported-by: Keith Busch <[email protected]>
Signed-off-by: Jan Kara <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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The memcpy() KUnit tests are trying to sanity-check run-time behaviors,
but tripped compile-time warnings about a pathological condition of a
too-small buffer being used for input. Avoid this by explicitly resizing
the buffer, but leaving the string short. Avoid the following warning:
lib/memcpy_kunit.c: In function 'strtomem_test':
include/linux/string.h:303:42: warning: 'strnlen' specified bound 4 exceeds source size 3 [-Wstringop-overread]
303 | memcpy(dest, src, min(_dest_len, strnlen(src, _dest_len))); \
include/linux/minmax.h:32:39: note: in definition of macro '__cmp_once'
32 | typeof(y) unique_y = (y); \
| ^
include/linux/minmax.h:45:25: note: in expansion of macro '__careful_cmp'
45 | #define min(x, y) __careful_cmp(x, y, <)
| ^~~~~~~~~~~~~
include/linux/string.h:303:27: note: in expansion of macro 'min'
303 | memcpy(dest, src, min(_dest_len, strnlen(src, _dest_len))); \
| ^~~
lib/memcpy_kunit.c:290:9: note: in expansion of macro 'strtomem'
290 | strtomem(wrap.output, input);
| ^~~~~~~~
lib/memcpy_kunit.c:275:27: note: source object allocated here
275 | static const char input[] = "hi";
| ^~~~~
Reported-by: kernel test robot <[email protected]>
Link: https://lore.kernel.org/linux-mm/[email protected]
Fixes: dfbafa70bde2 ("string: Introduce strtomem() and strtomem_pad()")
Signed-off-by: Kees Cook <[email protected]>
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Since the definition of is_signed_type() has been moved from
<linux/overflow.h> to <linux/compiler.h>, include the latter header file
instead of the former. Additionally, add a test for the type 'char'.
Cc: Isabella Basso <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Signed-off-by: Bart Van Assche <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Add lib/fortify_kunit.c KUnit test for checking the expected behavioral
characteristics of FORTIFY_SOURCE internals.
Cc: Nick Desaulniers <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Tom Rix <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: "Steven Rostedt (Google)" <[email protected]>
Cc: Yury Norov <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Sander Vanheule <[email protected]>
Cc: [email protected]
Cc: [email protected]
Reviewed-by: David Gow <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
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One of the "legitimate" uses of strncpy() is copying a NUL-terminated
string into a fixed-size non-NUL-terminated character array. To avoid
the weaknesses and ambiguity of intent when using strncpy(), provide
replacement functions that explicitly distinguish between trailing
padding and not, and require the destination buffer size be discoverable
by the compiler.
For example:
struct obj {
int foo;
char small[4] __nonstring;
char big[8] __nonstring;
int bar;
};
struct obj p;
/* This will truncate to 4 chars with no trailing NUL */
strncpy(p.small, "hello", sizeof(p.small));
/* p.small contains 'h', 'e', 'l', 'l' */
/* This will NUL pad to 8 chars. */
strncpy(p.big, "hello", sizeof(p.big));
/* p.big contains 'h', 'e', 'l', 'l', 'o', '\0', '\0', '\0' */
When the "__nonstring" attributes are missing, the intent of the
programmer becomes ambiguous for whether the lack of a trailing NUL
in the p.small copy is a bug. Additionally, it's not clear whether
the trailing padding in the p.big copy is _needed_. Both cases
become unambiguous with:
strtomem(p.small, "hello");
strtomem_pad(p.big, "hello", 0);
See also https://github.com/KSPP/linux/issues/90
Expand the memcpy KUnit tests to include these functions.
Cc: Wolfram Sang <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Guenter Roeck <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
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Under some pathological 32-bit configs, the shift overflow KUnit tests
create huge stack frames. Split up the function to avoid this,
separating by rough shift overflow cases.
Cc: Rasmus Villemoes <[email protected]>
Cc: Daniel Latypov <[email protected]>
Cc: Vitor Massaru Iha <[email protected]>
Cc: "Gustavo A. R. Silva" <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Reported-by: kernel test robot <[email protected]>
Link: https://lore.kernel.org/lkml/[email protected]
Acked-by: Daniel Latypov <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
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When the check_[op]_overflow() helpers were introduced, all arguments
were required to be the same type to make the fallback macros simpler.
However, now that the fallback macros have been removed[1], it is fine
to allow mixed types, which makes using the helpers much more useful,
as they can be used to test for type-based overflows (e.g. adding two
large ints but storing into a u8), as would be handy in the drm core[2].
Remove the restriction, and add additional self-tests that exercise
some of the mixed-type overflow cases, and double-check for accidental
macro side-effects.
[1] https://git.kernel.org/linus/4eb6bd55cfb22ffc20652732340c4962f3ac9a91
[2] https://lore.kernel.org/lkml/[email protected]
Cc: Rasmus Villemoes <[email protected]>
Cc: Gwan-gyeong Mun <[email protected]>
Cc: "Gustavo A. R. Silva" <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: [email protected]
Reviewed-by: Andrzej Hajda <[email protected]>
Reviewed-by: Gwan-gyeong Mun <[email protected]>
Tested-by: Gwan-gyeong Mun <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
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Demonstrate use of DECLARE_DYNDBG_CLASSMAP macro, and expose them as
sysfs-nodes for testing.
For each of the 4 class-map-types:
- declare a class-map of that type,
- declare the enum corresponding to those class-names
- share _base across 0..30 range
- add a __pr_debug_cls() call for each class-name
- declare 2 sysnodes for each class-map
for 'p' flag, and future 'T' flag
These declarations create the following sysfs parameter interface:
:#> pwd
/sys/module/test_dynamic_debug/parameters
:#> ls
T_disjoint_bits T_disjoint_names T_level_names T_level_num do_prints
p_disjoint_bits p_disjoint_names p_level_names p_level_num
NOTES:
The local wrapper macro is an api candidate, but there are already too
many parameters. OTOH, maybe related enum should be in there too,
since it has _base inter-dependencies.
The T_* params control the (future) T flag on the same class'd
pr_debug callsites as their p* counterparts. Using them will fail,
until the dyndbg-trace patches are added in.
:#> echo 1 > T_disjoint
[ 28.792489] dyndbg: disjoint: 0x1 > test_dynamic_debug.T_D2
[ 28.793848] dyndbg: query 0: "class D2_CORE +T" mod:*
[ 28.795086] dyndbg: split into words: "class" "D2_CORE" "+T"
[ 28.796467] dyndbg: op='+'
[ 28.797148] dyndbg: unknown flag 'T'
[ 28.798021] dyndbg: flags parse failed
[ 28.798947] dyndbg: processed 1 queries, with 0 matches, 1 errs
[ 28.800378] dyndbg: bit_0: -22 matches on class: D2_CORE -> 0x1
[ 28.801959] dyndbg: test_dynamic_debug.T_D2: updated 0x0 -> 0x1
[ 28.803974] dyndbg: total matches: -22
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Add kernel_param_ops and callbacks to use a class-map to validate and
apply input to a sysfs-node, which allows users to control classes
defined in that class-map. This supports uses like:
echo 0x3 > /sys/module/drm/parameters/debug
IE add these:
- int param_set_dyndbg_classes()
- int param_get_dyndbg_classes()
- struct kernel_param_ops param_ops_dyndbg_classes
Following the model of kernel/params.c STANDARD_PARAM_DEFS, these are
non-static and exported. This might be unnecessary here.
get/set use an augmented kernel_param; the arg refs a new struct
ddebug_class_param, which contains:
- A ptr to user's state-store; a union of &ulong for drm.debug, &int
for nouveau level debug. By ref'g the client's bit-state _var, code
coordinates with existing code (like drm_debug_enabled) which uses
it, so existing/remaining calls can work unchanged. Changing
drm.debug to a ulong allows use of BIT() etc.
- FLAGS: dyndbg.flags toggled by changes to bitmap. Usually just "p".
- MAP: a pointer to struct ddebug_classes_map, which maps those
class-names to .class_ids 0..N that the module is using. This
class-map is declared & initialized by DECLARE_DYNDBG_CLASSMAP.
- map-type: 4 enums DD_CLASS_TYPE_* select 2 input forms and 2 meanings.
numeric input:
DD_CLASS_TYPE_DISJOINT_BITS integer input, independent bits. ie: drm.debug
DD_CLASS_TYPE_LEVEL_NUM integer input, 0..N levels
classnames-list (comma separated) input:
DD_CLASS_TYPE_DISJOINT_NAMES each name affects a bit, others preserved
DD_CLASS_TYPE_LEVEL_NAMES names have level meanings, like kern_levels.h
_NAMES - comma-separated classnames (with optional +-)
_NUM - numeric input, 0-N expected
_BITS - numeric input, 0x1F bitmap form expected
_DISJOINT - bits are independent
_LEVEL - (x<y) on bit-pos.
_DISJOINT treats input like a bit-vector (ala drm.debug), and sets
each bit accordingly. LEVEL is layered on top of this.
_LEVEL treats input like a bit-pos:N, then sets bits(0..N)=1, and
bits(N+1..max)=0. This applies (bit<N) semantics on top of disjoint
bits.
USAGES:
A potentially typical _DISJOINT_NAMES use:
echo +DRM_UT_CORE,+DRM_UT_KMS,-DRM_UT_DRIVER,-DRM_UT_ATOMIC \
> /sys/module/drm/parameters/debug_catnames
A naive _LEVEL_NAMES use, with one class, that sets all in the
class-map according to (x<y):
: problem seen
echo +L7 > /sys/module/test_dynamic_debug/parameters/p_level_names
: problem solved
echo -L1 > /sys/module/test_dynamic_debug/parameters/p_level_names
Note this artifact:
: this is same as prev cmd (due to +/-)
echo L0 > /sys/module/test_dynamic_debug/parameters/p_level_names
: this is "even-more" off, but same wo __pr_debug_class(L0, "..").
echo -L0 > /sys/module/test_dynamic_debug/parameters/p_level_names
A stress-test/make-work usage (kid toggling a light switch):
echo +L7,L0,L7,L0,L7,L0,L7,L0,L7,L0,L7,L0,L7 \
> /sys/module/test_dynamic_debug/parameters/p_level_names
ddebug_apply_class_bitmap(): inside-fn, works on bitmaps, receives
new-bits, finds diffs vs client-bitvector holding "current" state,
and issues exec_query to commit the adjustment.
param_set_dyndbg_classes(): interface fn, sends _NAMES to
param_set_dyndbg_classnames() and returns, falls thru to handle _BITS,
_NUM internally, and calls ddebug_apply_class_bitmap(). Finishes by
updating state.
param_set_dyndbg_classnames(): handles classnames-list in loop, calls
ddebug_apply_class_bitmap for each, then updates state.
NOTES:
_LEVEL_ is overlay on _DISJOINT_; inputs are converted to a bitmask,
by the callbacks. IOW this is possible, and possibly confusing:
echo class V3 +p > control
echo class V1 -p > control
IMO thats ok, relative verbosity is an interface property.
_LEVEL_NUM maps still need class-names, even though the names are not
usable at the sysfs interface (unlike with _NAMES style). The names
are the only way to >control the classes.
- It must have a "V0" name,
something below "V1" to turn "V1" off.
__pr_debug_cls(V0,..) is printk, don't do that.
- "class names" is required at the >control interface.
- relative levels are not enforced at >control
_LEVEL_NAMES bear +/- signs, which alters the on-bit-pos by 1. IOW,
+L2 means L0,L1,L2, and -L2 means just L0,L1. This kinda spoils the
readback fidelity, since the L0 bit gets turned on by any use of any
L*, except "-L0".
All the interface uncertainty here pertains to the _NAMES features.
Nobody has actually asked for this, so its practical (if a little
tedious) to split it out.
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Add module-to-class validation:
#> echo class DRM_UT_KMS +p > /proc/dynamic_debug/control
If a query has "class FOO", then ddebug_find_valid_class(), called
from ddebug_change(), requires that FOO is known to module X,
otherwize the query is skipped entirely for X. This protects each
module's class-space, other than the default:31.
The authors' choice of FOO is highly selective, giving isolation
and/or coordinated sharing of FOOs. For example, only DRM modules
should know and respond to DRM_UT_KMS.
So this, combined with module's opt-in declaration of known classes,
effectively privatizes the .class_id space for each module (or
coordinated set of modules).
Notes:
For all "class FOO" queries, ddebug_find_valid_class() is called, it
returns the map matching the query, and sets valid_class via an
*outvar).
If no "class FOO" is supplied, valid_class = _CLASS_DFLT. This
insures that legacy queries do not trample on new class'd callsites,
as they get added.
Also add a new column to control-file output, displaying non-default
class-name (when found) or the "unknown _id:", if it has not been
(correctly) declared with one of the declarator macros.
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Add ddebug_attach_module_classes(), call it from ddebug_add_module().
It scans the classes/section its given, finds records where the
module-name matches the module being added, and adds them to the
module's maps list. No locking here, since the record
isn't yet linked into the ddebug_tables list.
It is called indirectly from 2 sources:
- from load_module(), where it scans the module's __dyndbg_classes
section, which contains DYNAMIC_DEBUG_CLASSES definitions from just
the module.
- from dynamic_debug_init(), where all DYNAMIC_DEBUG_CLASSES
definitions of each builtin module have been packed together.
This is why ddebug_attach_module_classes() checks module-name.
NOTES
Its (highly) likely that builtin classes will be ordered by module
name (just like prdbg descriptors are in the __dyndbg section). So
the list can be replaced by a vector (ptr + length), which will work
for loaded modules too. This would imitate whats currently done for
the _ddebug descriptors.
That said, converting to vector,len is close to pointless; a small
minority of modules will ever define a class-map, and almost all of
them will have only 1 or 2 class-maps, so theres only a couple dozen
pointers to save. TODO: re-evaluate for lines removable.
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Add __dyndbg_classes section, using __dyndbg as a model. Use it:
vmlinux.lds.h:
KEEP the new section, which also silences orphan section warning on
loadable modules. Add (__start_/__stop_)__dyndbg_classes linker
symbols for the c externs (below).
kernel/module/main.c:
- fill new fields in find_module_sections(), using section_objs()
- extend callchain prototypes
to pass classes, length
load_module(): pass new info to dynamic_debug_setup()
dynamic_debug_setup(): new params, pass through to ddebug_add_module()
dynamic_debug.c:
- add externs to the linker symbols.
ddebug_add_module():
- It currently builds a debug_table, and *will* find and attach classes.
dynamic_debug_init():
- add class fields to the _ddebug_info cursor var: di.
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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This new struct composes the linker provided (vector,len) section,
and provides a place to add other __dyndbg[] state-data later:
descs - the vector of descriptors in __dyndbg section.
num_descs - length of the data/section.
Use it, in several different ways, as follows:
In lib/dynamic_debug.c:
ddebug_add_module(): Alter params-list, replacing 2 args (array,index)
with a struct _ddebug_info * containing them both, with room for
expansion. This helps future-proof the function prototype against the
looming addition of class-map info into the dyndbg-state, by providing
a place to add more member fields later.
NB: later add static struct _ddebug_info builtins_state declaration,
not needed yet.
ddebug_add_module() is called in 2 contexts:
In dynamic_debug_init(), declare, init a struct _ddebug_info di
auto-var to use as a cursor. Then iterate over the prdbg blocks of
the builtin modules, and update the di cursor before calling
_add_module for each.
Its called from kernel/module/main.c:load_info() for each loaded
module:
In internal.h, alter struct load_info, replacing the dyndbg array,len
fields with an embedded _ddebug_info containing them both; and
populate its members in find_module_sections().
The 2 calling contexts differ in that _init deals with contiguous
subranges of __dyndbgs[] section, packed together, while loadable
modules are added one at a time.
So rename ddebug_add_module() into outer/__inner fns, call __inner
from _init, and provide the offset into the builtin __dyndbgs[] where
the module's prdbgs reside. The cursor provides start, len of the
subrange for each. The offset will be used later to pack the results
of builtin __dyndbg_sites[] de-duplication, and is 0 and unneeded for
loadable modules,
Note:
kernel/module/main.c includes <dynamic_debug.h> for struct
_ddeubg_info. This might be prone to include loops, since its also
included by printk.h. Nothing has broken in robot-land on this.
cc: Luis Chamberlain <[email protected]>
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
rework var-names for clarity, regularity
rename variables
- n to mod_sites - it counts sites-per-module
- entries to i - display only
- iter_start to iter_mod_start - marks start of each module's subrange
- modct to mod_ct - stylistic
new iterator var:
- site - cursor parallel to iter
1st step towards 'demotion' of iter->site, for removal later
treat vars as iters:
- drop init at top
init just above for-loop, in a textual block
Acked-by: Jason Baron <[email protected]>
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
This exported fn is unused, and will not be needed. Lets dump it.
The export was added to let drm control pr_debugs, as part of using
them to avoid drm_debug_enabled overheads. But its better to just
implement the drm.debug bitmap interface, then its available for
everyone.
Fixes: a2d375eda771 ("dyndbg: refine export, rename to dynamic_debug_exec_queries()")
Fixes: 4c0d77828d4f ("dyndbg: export ddebug_exec_queries")
Acked-by: Jason Baron <[email protected]>
Acked-by: Daniel Vetter <[email protected]>
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
Provide a simple module to allow testing DYNAMIC_DEBUG behavior. It
calls do_prints() from module-init, and with a sysfs-node.
dmesg -C
dmesg -w &
modprobe test_dynamic_debug dyndbg=+p
echo 1 > /sys/module/dynamic_debug/parameters/verbose
cat /sys/module/test_dynamic_debug/parameters/do_prints
echo module test_dynamic_debug +mftl > /proc/dynamic_debug/control
echo junk > /sys/module/test_dynamic_debug/parameters/do_prints
Acked-by: Jason Baron <[email protected]>
Acked-by: Daniel Vetter <[email protected]>
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
dyndbg's control-parser: ddebug_parse_query(), requires that search
terms: module, func, file, lineno, are used only once in a query; a
thing cannot be named both foo and bar.
The cited commit added an overriding module modname, taken from the
module loader, which is authoritative. So it set query.module 1st,
which disallowed its use in the query-string.
But now, its useful to allow a module-load to enable classes across a
whole (or part of) a subsystem at once.
# enable (dynamic-debug in) drm only
modprobe drm dyndbg="class DRM_UT_CORE +p"
# get drm_helper too
modprobe drm dyndbg="class DRM_UT_CORE module drm* +p"
# get everything that knows DRM_UT_CORE
modprobe drm dyndbg="class DRM_UT_CORE module * +p"
# also for boot-args:
drm.dyndbg="class DRM_UT_CORE module * +p"
So convert the override into a default, by filling it only when/after
the query-string omitted the module.
NB: the query class FOO handling is forthcoming.
Fixes: 8e59b5cfb9a6 dynamic_debug: add modname arg to exec_query callchain
Acked-by: Jason Baron <[email protected]>
Acked-by: Daniel Vetter <[email protected]>
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
`cat control` currently does octal escape, so '\n' becomes "\012".
Change this to display as "\n" instead, which reads much cleaner.
:#> head -n7 /proc/dynamic_debug/control
# filename:lineno [module]function flags format
init/main.c:1179 [main]initcall_blacklist =_ "blacklisting initcall %s\n"
init/main.c:1218 [main]initcall_blacklisted =_ "initcall %s blacklisted\n"
init/main.c:1424 [main]run_init_process =_ " with arguments:\n"
init/main.c:1426 [main]run_init_process =_ " %s\n"
init/main.c:1427 [main]run_init_process =_ " with environment:\n"
init/main.c:1429 [main]run_init_process =_ " %s\n"
Acked-by: Jason Baron <[email protected]>
Acked-by: Daniel Vetter <[email protected]>
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
Walk the module's vector of callsites backwards; ie N..0. This
"corrects" the backwards appearance of a module's prdbg vector when
walked 0..N. I think this is due to linker mechanics, which I'm
inclined to treat as immutable, and the order is fixable in display.
No functional changes.
Combined with previous commit, which reversed tables-list, we get:
:#> head -n7 /proc/dynamic_debug/control
# filename:lineno [module]function flags format
init/main.c:1179 [main]initcall_blacklist =_ "blacklisting initcall %s\012"
init/main.c:1218 [main]initcall_blacklisted =_ "initcall %s blacklisted\012"
init/main.c:1424 [main]run_init_process =_ " with arguments:\012"
init/main.c:1426 [main]run_init_process =_ " %s\012"
init/main.c:1427 [main]run_init_process =_ " with environment:\012"
init/main.c:1429 [main]run_init_process =_ " %s\012"
Acked-by: Jason Baron <[email protected]>
Acked-by: Daniel Vetter <[email protected]>
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
/proc/dynamic_debug/control walks the prdbg catalog in "reverse",
fix this by adding new ddebug_tables to tail of list.
This puts init/main.c entries 1st, which looks more than coincidental.
no functional changes.
Acked-by: Jason Baron <[email protected]>
Acked-by: Daniel Vetter <[email protected]>
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
print "old => new" flag values to the info("change") message.
no functional change.
Acked-by: Jason Baron <[email protected]>
Acked-by: Daniel Vetter <[email protected]>
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
In https://lore.kernel.org/lkml/[email protected]/
Vincent's patch commented on, and worked around, a bug toggling
static_branch's, when a 2nd PRINTK-ish flag was added. The bug
results in a premature static_branch_disable when the 1st of 2 flags
was disabled.
The cited commit computed newflags, but then in the JUMP_LABEL block,
failed to use that result, instead using just one of the terms in it.
Using newflags instead made the code work properly.
This is Vincents test-case, reduced. It needs the 2nd flag to
demonstrate the bug, but it's explanatory here.
pt_test() {
echo 5 > /sys/module/dynamic_debug/verbose
site="module tcp" # just one callsite
echo " $site =_ " > /proc/dynamic_debug/control # clear it
# A B ~A ~B
for flg in +T +p "-T #broke here" -p; do
echo " $site $flg " > /proc/dynamic_debug/control
done;
# A B ~B ~A
for flg in +T +p "-p #broke here" -T; do
echo " $site $flg " > /proc/dynamic_debug/control
done
}
pt_test
Fixes: 84da83a6ffc0 dyndbg: combine flags & mask into a struct, simplify with it
CC: [email protected]
Acked-by: Jason Baron <[email protected]>
Acked-by: Daniel Vetter <[email protected]>
Signed-off-by: Jim Cromie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
netlink allows to specify allowed ranges for integer types.
Unfortunately, nfnetlink passes integers in big endian, so the existing
NLA_POLICY_MAX() cannot be used.
At the moment, nfnetlink users, such as nf_tables, need to resort to
programmatic checking via helpers such as nft_parse_u32_check().
This is both cumbersome and error prone. This adds NLA_POLICY_MAX_BE
which adds range check support for BE16, BE32 and BE64 integers.
Signed-off-by: Florian Westphal <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
|
|
Add new helper function to allow for splitting specified user string
into a sequence of integers. Internally it makes use of get_options() so
the returned sequence contains the integers extracted plus an additional
element that begins the sequence and specifies the integers count.
Suggested-by: Andy Shevchenko <[email protected]>
Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Cezary Rojewski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Mark Brown <[email protected]>
|
|
We need the tty/serial fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
This reverts commit 16ede66973c84f890c03584f79158dd5b2d725f5.
This is causing issues with CPU stalls on my test box, revert it for
now until we understand what is going on. It looks like infinite
looping off sbitmap_queue_wake_up(), but hard to tell with a lot of
CPUs hitting this issue and the console scrolling infinitely.
Link: https://lore.kernel.org/linux-block/[email protected]/
Signed-off-by: Jens Axboe <[email protected]>
|
|
Batched completions can clear multiple bits, but we're only decrementing
the wait_cnt by one each time. This can cause waiters to never be woken,
stalling IO. Use the batched count instead.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215679
Signed-off-by: Keith Busch <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
|
|
devm_ioremap_np has never been used anywhere since it was added in early
2021, so remove it.
Signed-off-by: Christoph Hellwig <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
console_unblank() does this too (called in both places right after),
and with a lot more confidence inspiring approach to locking.
Reconstructing this story is very strange:
In b61312d353da ("oops handling: ensure that any oops is flushed to
the mtdoops console") it is claimed that a printk(" "); flushed out
the console buffer, which was removed in e3e8a75d2acf ("[PATCH]
Extract and use wake_up_klogd()"). In todays kernels this is done way
earlier in console_flush_on_panic with some really nasty tricks. I
didn't bother to fully reconstruct this all, least because the call to
bust_spinlock(0); gets moved every few years, depending upon how the
wind blows (or well, who screamed loudest about the various issue each
call site caused).
Before that commit the only calls to console_unblank() where in s390
arch code.
The other side here is the console->unblank callback, which was
introduced in 2.1.31 for the vt driver. Which predates the
console_unblank() function by a lot, which was added (without users)
in 2.4.14.3. So pretty much impossible to guess at any motivation
here. Also afaict the vt driver is the only (and always was the only)
console driver implementing the unblank callback, so no idea why a
call to console_unblank() was added for the mtdooops driver - the
action actually flushing out the console buffers is done from
console_unlock() only.
Note that as prep for the s390 users the locking was adjusted in
2.5.22 (I couldn't figure out how to properly reference the BK commit
from the historical git trees) from a normal semaphore to a trylock.
Note that a copy of the direct unblank_screen() call was added to
panic() in c7c3f05e341a ("panic: avoid deadlocks in re-entrant console
drivers"), which partially inlined the bust_spinlocks(0); call.
Long story short, I have no idea why the direct call to unblank_screen
survived for so long (the infrastructure to do it properly existed for
years), nor why it wasn't removed when the console_unblank() call was
finally added. But it makes a ton more sense to finally do that than
not - it's just better encapsulation to go through the console
functions instead of doing a direct call, so let's dare. Plus it
really does not make much sense to call the only unblank
implementation there is twice, once without, and once with appropriate
locking.
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: "Ilpo Järvinen" <[email protected]>
Cc: Tetsuo Handa <[email protected]>
Cc: Xuezhi Zhang <[email protected]>
Cc: Yangxi Xiang <[email protected]>
Cc: nick black <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Luis Chamberlain <[email protected]>
Cc: "Guilherme G. Piccoli" <[email protected]>
Cc: Marco Elver <[email protected]>
Cc: John Ogness <[email protected]>
Cc: Sebastian Andrzej Siewior <[email protected]>
Cc: David Gow <[email protected]>
Cc: tangmeng <[email protected]>
Cc: Tiezhu Yang <[email protected]>
Cc: Chris Wilson <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Acked-by: Sebastian Andrzej Siewior <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
Although not documented, is_signed_type() must support the 'bool' and
pointer types next to scalar and enumeration types. Add a selftest that
verifies that this macro handles all supported types correctly.
Cc: Andrew Morton <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Isabella Basso <[email protected]>
Cc: "Jason A. Donenfeld" <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Luc Van Oostenryck <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Cc: Sander Vanheule <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Yury Norov <[email protected]>
Signed-off-by: Bart Van Assche <[email protected]>
Tested-by: Isabella Basso <[email protected]>
Acked-by: Rasmus Villemoes <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fix from Herbert Xu:
"Fix a boot performance regression due to an unnecessary dependency on
XOR_BLOCKS"
* tag 'v6.0-p2' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: lib - remove unneeded selection of XOR_BLOCKS
|
|
Add KUnit test for hw_breakpoint constraints accounting, with various
interesting mixes of breakpoint targets (some care was taken to catch
interesting corner cases via bug-injection).
The test cannot be built as a module because it requires access to
hw_breakpoint_slots(), which is not inlinable or exported on all
architectures.
Signed-off-by: Marco Elver <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Dmitry Vyukov <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
|
|
Pull bitmap fixes from Yury Norov:
"Fix the reported issues, and implements the suggested improvements,
for the version of the cpumask tests [1] that was merged with commit
c41e8866c28c ("lib/test: introduce cpumask KUnit test suite").
These changes include fixes for the tests, and better alignment with
the KUnit style guidelines"
* tag 'bitmap-6.0-rc3' of github.com:/norov/linux:
lib/cpumask_kunit: add tests file to MAINTAINERS
lib/cpumask_kunit: log mask contents
lib/test_cpumask: follow KUnit style guidelines
lib/test_cpumask: fix cpu_possible_mask last test
lib/test_cpumask: drop cpu_possible_mask full test
|
|
If "nr + nr_tags <= map_depth", then the value of nr_tags will not be
greater than map_depth, so no additional comparison is required.
Signed-off-by: Liu Song <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
|
|
CRYPTO_LIB_CHACHA_GENERIC doesn't need to select XOR_BLOCKS. It perhaps
was thought that it's needed for __crypto_xor, but that's not the case.
Enabling XOR_BLOCKS is problematic because the XOR_BLOCKS code runs a
benchmark when it is initialized. That causes a boot time regression on
systems that didn't have it enabled before.
Therefore, remove this unnecessary and problematic selection.
Fixes: e56e18985596 ("lib/crypto: add prompts back to crypto libraries")
Cc: [email protected]
Signed-off-by: Eric Biggers <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from ipsec and netfilter (with one broken Fixes tag).
Current release - new code bugs:
- dsa: don't dereference NULL extack in dsa_slave_changeupper()
- dpaa: fix <1G ethernet on LS1046ARDB
- neigh: don't call kfree_skb() under spin_lock_irqsave()
Previous releases - regressions:
- r8152: fix the RX FIFO settings when suspending
- dsa: microchip: keep compatibility with device tree blobs with no
phy-mode
- Revert "net: macsec: update SCI upon MAC address change."
- Revert "xfrm: update SA curlft.use_time", comply with RFC 2367
Previous releases - always broken:
- netfilter: conntrack: work around exceeded TCP receive window
- ipsec: fix a null pointer dereference of dst->dev on a metadata dst
in xfrm_lookup_with_ifid
- moxa: get rid of asymmetry in DMA mapping/unmapping
- dsa: microchip: make learning configurable and keep it off while
standalone
- ice: xsk: prohibit usage of non-balanced queue id
- rxrpc: fix locking in rxrpc's sendmsg
Misc:
- another chunk of sysctl data race silencing"
* tag 'net-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (87 commits)
net: lantiq_xrx200: restore buffer if memory allocation failed
net: lantiq_xrx200: fix lock under memory pressure
net: lantiq_xrx200: confirm skb is allocated before using
net: stmmac: work around sporadic tx issue on link-up
ionic: VF initial random MAC address if no assigned mac
ionic: fix up issues with handling EAGAIN on FW cmds
ionic: clear broken state on generation change
rxrpc: Fix locking in rxrpc's sendmsg
net: ethernet: mtk_eth_soc: fix hw hash reporting for MTK_NETSYS_V2
MAINTAINERS: rectify file entry in BONDING DRIVER
i40e: Fix incorrect address type for IPv6 flow rules
ixgbe: stop resetting SYSTIME in ixgbe_ptp_start_cyclecounter
net: Fix a data-race around sysctl_somaxconn.
net: Fix a data-race around netdev_unregister_timeout_secs.
net: Fix a data-race around gro_normal_batch.
net: Fix data-races around sysctl_devconf_inherit_init_net.
net: Fix data-races around sysctl_fb_tunnels_only_for_init_net.
net: Fix a data-race around netdev_budget_usecs.
net: Fix data-races around sysctl_max_skb_frags.
net: Fix a data-race around netdev_budget.
...
|
|
There is no modification for param bitmap in function
bitmap_string() and bitmap_list_string(), so add const
modifier for it.
Signed-off-by: Jian Shen <[email protected]>
Signed-off-by: Guangbin Huang <[email protected]>
Reviewed-by: Steven Rostedt (Google) <[email protected]>
Reviewed-by: Sergey Senozhatsky <[email protected]>
Signed-off-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
|
|
For extra context, log the contents of the masks under test. This
should help with finding out why a certain test fails.
Link: https://lore.kernel.org/lkml/CABVgOSkPXBc-PWk1zBZRQ_Tt+Sz1ruFHBj3ixojymZF=Vi4tpQ@mail.gmail.com/
Suggested-by: David Gow <[email protected]>
Signed-off-by: Sander Vanheule <[email protected]>
Signed-off-by: Yury Norov <[email protected]>
|
|
The cpumask test suite doesn't follow the KUnit style guidelines, as
laid out in Documentation/dev-tools/kunit/style.rst. The file is
renamed to lib/cpumask_kunit.c to clearly distinguish it from other,
non-KUnit, tests.
Link: https://lore.kernel.org/lkml/[email protected]/
Suggested-by: Maíra Canal <[email protected]>
Signed-off-by: Sander Vanheule <[email protected]>
Reviewed-by: Maíra Canal <[email protected]>
Reviewed-by: David Gow <[email protected]>
Acked-by: Yury Norov <[email protected]>
Signed-off-by: Yury Norov <[email protected]>
|
|
Since cpumask_first() on the cpu_possible_mask must return at most
nr_cpu_ids - 1 for a valid result, cpumask_last() cannot return anything
larger than this value. As test_cpumask_weight() also verifies that the
total weight of cpu_possible_mask must equal nr_cpu_ids, the last bit
set in this mask must be at nr_cpu_ids - 1.
Fixes: c41e8866c28c ("lib/test: introduce cpumask KUnit test suite")
Link: https://lore.kernel.org/lkml/[email protected]/
Reported-by: Maíra Canal <[email protected]>
Signed-off-by: Sander Vanheule <[email protected]>
Tested-by: Maíra Canal <[email protected]>
Reviewed-by: David Gow <[email protected]>
Acked-by: Yury Norov <[email protected]>
Signed-off-by: Yury Norov <[email protected]>
|
|
When the number of CPUs that can possibly be brought online is known at
boot time, e.g. when HOTPLUG is disabled, nr_cpu_ids may be smaller than
NR_CPUS. In that case, cpu_possible_mask would not be completely filled,
and cpumask_full(cpu_possible_mask) can return false for valid system
configurations.
Without this test, cpu_possible_mask contents are still constrained by
a check on cpumask_weight(), as well as tests in test_cpumask_first(),
test_cpumask_last(), test_cpumask_next(), and test_cpumask_iterators().
Fixes: c41e8866c28c ("lib/test: introduce cpumask KUnit test suite")
Link: https://lore.kernel.org/lkml/[email protected]/
Reported-by: Maíra Canal <[email protected]>
Signed-off-by: Sander Vanheule <[email protected]>
Tested-by: Maíra Canal <[email protected]>
Reviewed-by: David Gow <[email protected]>
Signed-off-by: Yury Norov <[email protected]>
|
|
While reading rs->interval and rs->burst, they can be changed
concurrently via sysctl (e.g. net_ratelimit_state). Thus, we
need to add READ_ONCE() to their readers.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
|
|
There are two problems can lead to lost wakeup:
1) invalid wakeup on the wrong waitqueue:
For example, 2 * wake_batch tags are put, while only wake_batch threads
are woken:
__sbq_wake_up
atomic_cmpxchg -> reset wait_cnt
__sbq_wake_up -> decrease wait_cnt
...
__sbq_wake_up -> wait_cnt is decreased to 0 again
atomic_cmpxchg
sbq_index_atomic_inc -> increase wake_index
wake_up_nr -> wake up and waitqueue might be empty
sbq_index_atomic_inc -> increase again, one waitqueue is skipped
wake_up_nr -> invalid wake up because old wakequeue might be empty
To fix the problem, increasing 'wake_index' before resetting 'wait_cnt'.
2) 'wait_cnt' can be decreased while waitqueue is empty
As pointed out by Jan Kara, following race is possible:
CPU1 CPU2
__sbq_wake_up __sbq_wake_up
sbq_wake_ptr() sbq_wake_ptr() -> the same
wait_cnt = atomic_dec_return()
/* decreased to 0 */
sbq_index_atomic_inc()
/* move to next waitqueue */
atomic_set()
/* reset wait_cnt */
wake_up_nr()
/* wake up on the old waitqueue */
wait_cnt = atomic_dec_return()
/*
* decrease wait_cnt in the old
* waitqueue, while it can be
* empty.
*/
Fix the problem by waking up before updating 'wake_index' and
'wait_cnt'.
With this patch, noted that 'wait_cnt' is still decreased in the old
empty waitqueue, however, the wakeup is redirected to a active waitqueue,
and the extra decrement on the old empty waitqueue is not handled.
Fixes: 88459642cba4 ("blk-mq: abstract tag allocation out into sbitmap library")
Signed-off-by: Yu Kuai <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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No architecture actually defines this, so it's unneeded.
Signed-off-by: Eric Biggers <[email protected]>
Reviewed-by: Jason A. Donenfeld <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
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CRYPTO_LIB_CHACHA depends on CRYPTO for __crypto_xor, defined in
crypto/algapi.c. This is a layering violation because the dependencies
should only go in the other direction (crypto/ => lib/crypto/). Also
the correct dependency would be CRYPTO_ALGAPI, not CRYPTO. Fix this by
moving __crypto_xor into the utils module in lib/crypto/.
Note that CRYPTO_LIB_CHACHA_GENERIC selected XOR_BLOCKS, which is
unrelated and unnecessary. It was perhaps thought that XOR_BLOCKS was
needed for __crypto_xor, but that's not the case.
Signed-off-by: Eric Biggers <[email protected]>
Reviewed-by: Jason A. Donenfeld <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
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