05 Aug, 2020
1 commit
-
Pull documentation updates from Jonathan Corbet:
"It's been a busy cycle for documentation - hopefully the busiest for a
while to come. Changes include:- Some new Chinese translations
- Progress on the battle against double words words and non-HTTPS
URLs- Some block-mq documentation
- More RST conversions from Mauro. At this point, that task is
essentially complete, so we shouldn't see this kind of churn again
for a while. Unless we decide to switch to asciidoc or
something...:)- Lots of typo fixes, warning fixes, and more"
* tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits)
scripts/kernel-doc: optionally treat warnings as errors
docs: ia64: correct typo
mailmap: add entry for
doc/zh_CN: add cpu-load Chinese version
Documentation/admin-guide: tainted-kernels: fix spelling mistake
MAINTAINERS: adjust kprobes.rst entry to new location
devices.txt: document rfkill allocation
PCI: correct flag name
docs: filesystems: vfs: correct flag name
docs: filesystems: vfs: correct sync_mode flag names
docs: path-lookup: markup fixes for emphasis
docs: path-lookup: more markup fixes
docs: path-lookup: fix HTML entity mojibake
CREDITS: Replace HTTP links with HTTPS ones
docs: process: Add an example for creating a fixes tag
doc/zh_CN: add Chinese translation prefer section
doc/zh_CN: add clearing-warn-once Chinese version
doc/zh_CN: add admin-guide index
doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label
futex: MAINTAINERS: Re-add selftests directory
...
24 Jul, 2020
1 commit
-
Fix the following warning:
WARNING: Definition list ends without a blank line;
unexpected unindent.By switching to the literal block syntax.
Signed-off-by: Daniel W. S. Almeida
Link: https://lore.kernel.org/r/20200718165107.625847-8-dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet
03 Jul, 2020
1 commit
-
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.Signed-off-by: Alexander A. Klimov
Reviewed-by: Petr Mladek
Reviewed-by: Sergey Senozhatsky
Signed-off-by: Petr Mladek
Link: https://lore.kernel.org/r/20200702200536.13389-1-grandmaster@al2klimov.de
02 Jun, 2020
2 commits
-
Pull documentation updates from Jonathan Corbet:
"A fair amount of stuff this time around, dominated by yet another
massive set from Mauro toward the completion of the RST conversion. I
*really* hope we are getting close to the end of this. Meanwhile,
those patches reach pretty far afield to update document references
around the tree; there should be no actual code changes there. There
will be, alas, more of the usual trivial merge conflicts.Beyond that we have more translations, improvements to the sphinx
scripting, a number of additions to the sysctl documentation, and lots
of fixes"* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
Documentation: fixes to the maintainer-entry-profile template
zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
tracing: Fix events.rst section numbering
docs: acpi: fix old http link and improve document format
docs: filesystems: add info about efivars content
Documentation: LSM: Correct the basic LSM description
mailmap: change email for Ricardo Ribalda
docs: sysctl/kernel: document unaligned controls
Documentation: admin-guide: update bug-hunting.rst
docs: sysctl/kernel: document ngroups_max
nvdimm: fixes to maintainter-entry-profile
Documentation/features: Correct RISC-V kprobes support entry
Documentation/features: Refresh the arch support status files
Revert "docs: sysctl/kernel: document ngroups_max"
docs: move locking-specific documents to locking/
docs: move digsig docs to the security book
docs: move the kref doc into the core-api book
docs: add IRQ documentation at the core-api book
docs: debugging-via-ohci1394.txt: add it to the core-api book
docs: fix references for ipmi.rst file
... -
Pull printk updates from Petr Mladek:
- Benjamin Herrenschmidt solved a problem with non-matched console
aliases by first checking consoles defined on the command line. It is
a more conservative approach than the previous attempts.- Benjamin also made sure that the console accessible via /dev/console
always has CON_CONSDEV flag.- Andy Shevchenko added the %ptT modifier for printing struct time64_t.
It extends the existing %ptR handling for struct rtc_time.- Bruno Meneguele fixed /dev/kmsg error value returned by unsupported
SEEK_CUR.- Tetsuo Handa removed unused pr_cont_once().
... and a few small fixes.
* tag 'printk-for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk: Remove pr_cont_once()
printk: handle blank console arguments passed in.
kernel/printk: add kmsg SEEK_CUR handling
printk: Fix a typo in comment "interator"->"iterator"
usb: pulse8-cec: Switch to use %ptT
ARM: bcm2835: Switch to use %ptT
lib/vsprintf: Print time64_t in human readable format
lib/vsprintf: update comment about simple_strto() functions
printk: Correctly set CON_CONSDEV even when preferred console was not registered
printk: Fix preferred console selection with multiple matches
printk: Move console matching logic into a separate function
printk: Convert a use of sprintf to snprintf in console_unlock
20 May, 2020
1 commit
-
There are users which print time and date represented by content of
time64_t type in human readable format.Instead of open coding that each time introduce %ptT[dt][r] specifier.
Few test cases for %ptT specifier has been added as well.
Link: https://lore.kernel.org/r/20200415170046.33374-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko
Reviewed-by: Alexandre Belloni
Acked-by: Sergey Senozhatsky
Rewieved-by: Petr Mladek
Signed-off-by: Petr Mladek
15 May, 2020
1 commit
-
Usage of plain %s conversion specifier in bpf_trace_printk() suffers from the
very same issue as bpf_probe_read{,str}() helpers, that is, it is broken on
archs with overlapping address ranges.While the helpers have been addressed through work in 6ae08ae3dea2 ("bpf: Add
probe_read_{user, kernel} and probe_read_{user, kernel}_str helpers"), we need
an option for bpf_trace_printk() as well to fix it.Similarly as with the helpers, force users to make an explicit choice by adding
%pks and %pus specifier to bpf_trace_printk() which will then pick the corresponding
strncpy_from_unsafe*() variant to perform the access under KERNEL_DS or USER_DS.
The %pk* (kernel specifier) and %pu* (user specifier) can later also be extended
for other objects aside strings that are probed and printed under tracing, and
reused out of other facilities like bpf_seq_printf() or BTF based type printing.Existing behavior of %s for current users is still kept working for archs where it
is not broken and therefore gated through CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE.
For archs not having this property we fall-back to pick probing under KERNEL_DS as
a sensible default.Fixes: 8d3b7dce8622 ("bpf: add support for %s specifier to bpf_trace_printk()")
Reported-by: Linus Torvalds
Reported-by: Christoph Hellwig
Signed-off-by: Daniel Borkmann
Signed-off-by: Alexei Starovoitov
Cc: Masami Hiramatsu
Cc: Brendan Gregg
Link: https://lore.kernel.org/bpf/20200515101118.6508-4-daniel@iogearbox.net
21 Apr, 2020
1 commit
-
Add kerneldocs comments to the pr_*() macros in printk.h.
Add a new rst node in the core-api manual describing the basic usage of
printk and the related macro aliases.Signed-off-by: Ricardo Cañuelo
Link: https://lore.kernel.org/r/20200403093617.18003-1-ricardo.canuelo@collabora.com
Signed-off-by: Jonathan Corbet
03 Dec, 2019
1 commit
-
Pull Documentation updates from Jonathan Corbet:
"Here are the main documentation changes for 5.5:- Various kerneldoc script enhancements.
- More RST conversions; those are slowing down as we run out of
things to convert, but we're a ways from done still.- Dan's "maintainer profile entry" work landed at last. Now we just
need to get maintainers to fill in the profiles...- A reworking of the parallel build setup to work better with a
variety of systems (and to not take over huge systems entirely in
particular).- The MAINTAINERS file is now converted to RST during the build.
Hopefully nobody ever tries to print this thing, or they will need
to load a lot of paper.- A script and documentation making it easy for maintainers to add
Link: tags at commit time.Also included is the removal of a bunch of spurious CR characters"
* tag 'docs-5.5a' of git://git.lwn.net/linux: (91 commits)
docs: remove a bunch of stray CRs
docs: fix up the maintainer profile document
libnvdimm, MAINTAINERS: Maintainer Entry Profile
Maintainer Handbook: Maintainer Entry Profile
MAINTAINERS: Reclaim the P: tag for Maintainer Entry Profile
docs, parallelism: Rearrange how jobserver reservations are made
docs, parallelism: Do not leak blocking mode to other readers
docs, parallelism: Fix failure path and add comment
Documentation: Remove bootmem_debug from kernel-parameters.txt
Documentation: security: core.rst: fix warnings
Documentation/process/howto/kokr: Update for 4.x -> 5.x versioning
Documentation/translation: Use Korean for Korean translation title
docs/memory-barriers.txt: Remove remaining references to mmiowb()
docs/memory-barriers.txt/kokr: Update I/O section to be clearer about CPU vs thread
docs/memory-barriers.txt/kokr: Fix style, spacing and grammar in I/O section
Documentation/kokr: Kill all references to mmiowb()
docs/memory-barriers.txt/kokr: Rewrite "KERNEL I/O BARRIER EFFECTS" section
docs: Add initial documentation for devfreq
Documentation: Document how to get links with git am
docs: Add request_irq() documentation
...
27 Nov, 2019
1 commit
-
Pull device properties framework updates from Rafael Wysocki:
"Add support for printing fwnode names using a new conversion specifier
"%pfw" (Sakari Ailus), clean up the software node and
efi/apple-properties code in preparation for improved software node
reference properties handling (Dmitry Torokhov) and fix the struct
fwnode_operations description (Heikki Krogerus)"* tag 'devprop-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (22 commits)
software node: simplify property_entry_read_string_array()
software node: unify PROPERTY_ENTRY_XXX macros
software node: remove property_entry_read_uNN_array functions
software node: get rid of property_set_pointer()
software node: clean up property_copy_string_array()
software node: mark internal macros with double underscores
efi/apple-properties: use PROPERTY_ENTRY_U8_ARRAY_LEN
software node: introduce PROPERTY_ENTRY_XXX_ARRAY_LEN()
software node: remove DEV_PROP_MAX
device property: Fix the description of struct fwnode_operations
lib/test_printf: Add tests for %pfw printk modifier
lib/vsprintf: Add %pfw conversion specifier for printing fwnode names
lib/vsprintf: OF nodes are first and foremost, struct device_nodes
lib/vsprintf: Make use of fwnode API to obtain node names and separators
lib/vsprintf: Add a note on re-using %pf or %pF
lib/vsprintf: Remove support for %pF and %pf in favour of %pS and %ps
device property: Add a function to obtain a node's prefix
device property: Add fwnode_get_name for returning the name of a node
device property: Add functions for accessing node's parents
device property: Move fwnode_get_parent() up
...
26 Nov, 2019
1 commit
-
Pull printk updates from Petr Mladek:
- Allow to print symbolic error names via new %pe modifier.
- Use pr_warn() instead of the remaining pr_warning() calls. Fix
formatting of the related lines.- Add VSPRINTF entry to MAINTAINERS.
* tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (32 commits)
checkpatch: don't warn about new vsprintf pointer extension '%pe'
MAINTAINERS: Add VSPRINTF
tools lib api: Renaming pr_warning to pr_warn
ASoC: samsung: Use pr_warn instead of pr_warning
lib: cpu_rmap: Use pr_warn instead of pr_warning
trace: Use pr_warn instead of pr_warning
dma-debug: Use pr_warn instead of pr_warning
vgacon: Use pr_warn instead of pr_warning
fs: afs: Use pr_warn instead of pr_warning
sh/intc: Use pr_warn instead of pr_warning
scsi: Use pr_warn instead of pr_warning
platform/x86: intel_oaktrail: Use pr_warn instead of pr_warning
platform/x86: asus-laptop: Use pr_warn instead of pr_warning
platform/x86: eeepc-laptop: Use pr_warn instead of pr_warning
oprofile: Use pr_warn instead of pr_warning
of: Use pr_warn instead of pr_warning
macintosh: Use pr_warn instead of pr_warning
idsn: Use pr_warn instead of pr_warning
ide: Use pr_warn instead of pr_warning
crypto: n2: Use pr_warn instead of pr_warning
...
08 Nov, 2019
1 commit
-
When print the difference between two pointers, we should use
the ptrdiff_t modifier %t.Signed-off-by: Miles Chen
Signed-off-by: Jonathan Corbet
17 Oct, 2019
1 commit
-
It has been suggested several times to extend vsnprintf() to be able
to convert the numeric value of ENOSPC to print "ENOSPC". This
implements that as a %p extension: With %pe, one can doif (IS_ERR(foo)) {
pr_err("Sorry, can't do that: %pe\n", foo);
return PTR_ERR(foo);
}instead of what is seen in quite a few places in the kernel:
if (IS_ERR(foo)) {
pr_err("Sorry, can't do that: %ld\n", PTR_ERR(foo));
return PTR_ERR(foo);
}If the value passed to %pe is an ERR_PTR, but the library function
errname() added here doesn't know about the value, the value is simply
printed in decimal. If the value passed to %pe is not an ERR_PTR, we
treat it as an ordinary %p and thus print the hashed value (passing
non-ERR_PTR values to %pe indicates a bug in the caller, but we can't
do much about that).With my embedded hat on, and because it's not very invasive to do,
I've made it possible to remove this. The errname() function and
associated lookup tables take up about 3K. For most, that's probably
quite acceptable and a price worth paying for more readable
dmesg (once this starts getting used), while for those that disable
printk() it's of very little use - I don't see a
procfs/sysfs/seq_printf() file reasonably making use of this - and
they clearly want to squeeze vmlinux as much as possible. Hence the
default y if PRINTK.The symbols to include have been found by massaging the output of
find arch include -iname 'errno*.h' | xargs grep -E 'define\s*E'
In the cases where some common aliasing exists
(e.g. EAGAIN=EWOULDBLOCK on all platforms, EDEADLOCK=EDEADLK on most),
I've moved the more popular one (in terms of 'git grep -w Efoo | wc)
to the bottom so that one takes precedence.Link: http://lkml.kernel.org/r/20191015190706.15989-1-linux@rasmusvillemoes.dk
To: "Jonathan Corbet"
To: linux-kernel@vger.kernel.org
Cc: "Andy Shevchenko"
Cc: "Andrew Morton"
Cc: "Joe Perches"
Cc: linux-doc@vger.kernel.org
Signed-off-by: Rasmus Villemoes
Acked-by: Uwe Kleine-König
Reviewed-by: Petr Mladek
[andy.shevchenko@gmail.com: use abs()]
Acked-by: Andy Shevchenko
Signed-off-by: Petr Mladek
11 Oct, 2019
2 commits
-
Add support for %pfw conversion specifier (with "f" and "P" modifiers) to
support printing full path of the node, including its name ("f") and only
the node's name ("P") in the printk family of functions. The two flags
have equivalent functionality to existing %pOF with the same two modifiers
("f" and "P") on OF based systems. The ability to do the same on ACPI
based systems is added by this patch.On ACPI based systems the resulting strings look like
\_SB.PCI0.CIO2.port@1.endpoint@0
where the nodes are separated by a dot (".") and the first three are
ACPI device nodes and the latter two ACPI data nodes.Signed-off-by: Sakari Ailus
Reviewed-by: Andy Shevchenko
Reviewed-by: Petr Mladek
Signed-off-by: Rafael J. Wysocki -
%pS and %ps are now the preferred conversion specifiers to print function
names. The functionality is equivalent; remove the old, deprecated %pF
and %pf support.Depends-on: commit 2d44d165e939 ("scsi: lpfc: Convert existing %pf users to %ps")
Depends-on: commit b295c3e39c13 ("tools lib traceevent: Convert remaining %p[fF] users to %p[sS]")
Signed-off-by: Sakari Ailus
Reviewed-by: Andy Shevchenko
Reviewed-by: Petr Mladek
Signed-off-by: Rafael J. Wysocki
14 Sep, 2019
1 commit
-
Standard integer promotion is already done and %hx and %hhx is useless
so do not encourage the use of %hh[xudi] or %h[xudi].As Linus said in:
https://lore.kernel.org/lkml/CAHk-=wgoxnmsj8GEVFJSvTwdnWm8wVJthefNk2n6+4TC=20e0Q@mail.gmail.com/It's a pointless warning, making for more complex code, and
making people remember esoteric printf format details that have no
reason for existing.The "h" and "hh" things should never be used. The only reason for them
being used if if you have an "int", but you want to print it out as a
"char" (and honestly, that is a really bad reason, you'd be better off
just using a proper cast to make the code more obvious).So if what you have a "char" (or unsigned char) you should always just
print it out as an "int", knowing that the compiler already did the
proper type conversion.Signed-off-by: Joe Perches
Reviewed-by: Louis Taylor
Signed-off-by: Jonathan Corbet
15 Jul, 2019
2 commits
-
The stuff under sysctl describes /sys interface from userspace
point of view. So, add it to the admin-guide and remove the
:orphan: from its index file.Signed-off-by: Mauro Carvalho Chehab
-
Rename the /proc/sys/ documentation files to ReST, using the
README file as a template for an index.rst, adding the other
files there via TOC markup.Despite being written on different times with different
styles, try to make them somewhat coherent with a similar
look and feel, ensuring that they'll look nice as both
raw text file and as via the html output produced by the
Sphinx build system.At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.Signed-off-by: Mauro Carvalho Chehab
26 Apr, 2019
2 commits
-
We are able to detect invalid values handled by %p[iI] printk specifier.
The current error message is "invalid address". It might cause confusion
against "(efault)" reported by the generic valid_pointer_address() check.Let's unify the style and use the more appropriate error code description
"(einval)".Link: http://lkml.kernel.org/r/20190417115350.20479-10-pmladek@suse.com
To: Rasmus Villemoes
Cc: Linus Torvalds
Cc: "Tobin C . Harding"
Cc: Joe Perches
Cc: Andrew Morton
Cc: Michal Hocko
Cc: Steven Rostedt
Cc: Sergey Senozhatsky
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Sergey Senozhatsky
Reviewed-by: Andy Shevchenko
Signed-off-by: Petr Mladek -
We already prevent crash when dereferencing some obviously broken
pointers. But the handling is not consistent. Sometimes we print "(null)"
only for pure NULL pointer, sometimes for pointers in the first
page and sometimes also for pointers in the last page (error codes).Note that printk() call this code under logbuf_lock. Any recursive
printks are redirected to the printk_safe implementation and the messages
are stored into per-CPU buffers. These buffers might be eventually flushed
in printk_safe_flush_on_panic() but it is not guaranteed.This patch adds a check using probe_kernel_read(). It is not a full-proof
test. But it should help to see the error message in 99% situations where
the kernel would silently crash otherwise.Also it makes the error handling unified for "%s" and the many %p*
specifiers that need to read the data from a given address. We print:+ (null) when accessing data on pure pure NULL address
+ (efault) when accessing data on an invalid addressIt does not affect the %p* specifiers that just print the given address
in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p.Note that we print (efault) from security reasons. In fact, the real
address can be seen only by %px or eventually %pK.Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com
To: Rasmus Villemoes
Cc: Linus Torvalds
Cc: "Tobin C . Harding"
Cc: Joe Perches
Cc: Andrew Morton
Cc: Michal Hocko
Cc: Steven Rostedt
Cc: Sergey Senozhatsky
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Sergey Senozhatsky
Reviewed-by: Andy Shevchenko
Signed-off-by: Petr Mladek
10 Mar, 2019
1 commit
-
Pull printk updates from Petr Mladek:
- Allow to sort mixed lines by an extra information about the caller
- Remove no longer used LOG_PREFIX.
- Some clean up and documentation update.
* tag 'printk-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
printk/docs: Add extra integer types to printk-formats
printk: Remove no longer used LOG_PREFIX.
lib/vsprintf: Remove %pCr remnant in comment
printk: Pass caller information to log_store().
printk: Add caller information to printk() output.
04 Mar, 2019
1 commit
-
A few commonly used integer types were absent from this table, so add
them.Link: https://github.com/ClangBuiltLinux/linux/issues/378
Suggested-by: Nick Desaulniers
Link: http://lkml.kernel.org/r/20190303123647.22020-1-louis@kragniz.eu
Cc: pmladek@suse.com
Cc: geert+renesas@glider.be
Cc: andriy.shevchenko@linux.intel.com
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: clang-built-linux@googlegroups.com
Cc: ndesaulniers@google.com
Cc: jflat@chromium.org
Cc: Louis Taylor
Signed-off-by: Louis Taylor
[pmladek@suse.com: sorted both variants the same way by size]
Signed-off-by: Petr Mladek
11 Dec, 2018
1 commit
-
There are users which print time and date represented by content of
struct rtc_time in human readable format.Instead of open coding that each time introduce %ptR[dt][r] specifier.
Cc: Arnd Bergmann
Cc: Bartlomiej Zolnierkiewicz
Cc: Dmitry Torokhov
Cc: Geert Uytterhoeven
Cc: Guan Xuetao
Cc: Ingo Molnar
Cc: Jason Wessel
Cc: Jonathan Corbet
Cc: Jonathan Hunter
Cc: Krzysztof Kozlowski
Cc: "Rafael J. Wysocki"
Cc: Thierry Reding
Cc: Petr Mladek
Signed-off-by: Andy Shevchenko
Reviewed-by: Petr Mladek
Signed-off-by: Alexandre Belloni
26 Oct, 2018
1 commit
-
Pull printk updates from Petr Mladek:
- Fix two more locations where printf formatting leaked pointers
- Better log_buf_len parameter handling
- Add prefix to messages from printk code
- Do not miss messages on other consoles when the log is replayed on a
new one- Reduce race between console registration and panic() when the log
might get replayed on all consoles- Some cont buffer code clean up
- Call console only when there is something to do (log vs cont buffer)
* tag 'printk-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
lib/vsprintf: Hash printed address for netdev bits fallback
lib/vsprintf: Hash legacy clock addresses
lib/vsprintf: Prepare for more general use of ptr_to_id()
lib/vsprintf: Make ptr argument conts in ptr_to_id()
printk: fix integer overflow in setup_log_buf()
printk: do not preliminary split up cont buffer
printk: lock/unlock console only for new logbuf entries
printk: keep kernel cont support always enabled
printk: Give error on attempt to set log buffer length to over 2G
printk: Add KBUILD_MODNAME and remove a redundant print prefix
printk: Correct wrong casting
printk: Fix panic caused by passing log_buf_len to command line
printk: CON_PRINTBUFFER console registration is a bit racy
printk: Do not miss new messages when replaying the log
13 Oct, 2018
1 commit
-
When converting from text to rst, the kobjects section and its sole
subsection about device tree nodes were coalesced into a single section,
yielding an inconsistent result.Remove all references to kobjects, as
1. Device tree object pointers are not compatible to kobject pointers
(the former may embed the latter, though), and
2. there are no printk formats defined for kobject types.Update the vsprintf() source code comments to match the above.
Fixes: b3ed23213eab1e08 ("doc: convert printk-formats.txt to rst")
Signed-off-by: Geert Uytterhoeven
Signed-off-by: Jonathan Corbet
12 Oct, 2018
1 commit
-
On platforms using the Common Clock Framework, "%pC" prints the clock's
name. On legacy platforms, it prints the unhashed clock's address,
potentially leaking sensitive information regarding the kernel layout in
memory.Avoid this leak by printing the hashed address instead. To distinguish
between clocks, a 32-bit unique identifier is as good as an actual
pointer value.Fixes: ad67b74d2469d9b8 ("printk: hash addresses printed with %p")
Link: http://lkml.kernel.org/r/20181011084249.4520-3-geert+renesas@glider.be
To: "Tobin C . Harding"
To: Andrew Morton
To: Jonathan Corbet
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Geert Uytterhoeven
Reviewed-by: Andy Shevchenko
Signed-off-by: Petr Mladek
05 Jun, 2018
1 commit
-
"%pCr" formats the current rate of a clock, and calls clk_get_rate().
The latter obtains a mutex, hence it must not be called from atomic
context.Remove support for this rarely-used format, as vsprintf() (and e.g.
printk()) must be callable from any context.Any remaining out-of-tree users will start seeing the clock's name
printed instead of its rate.Reported-by: Jia-Ju Bai
Fixes: 900cca2944254edd ("lib/vsprintf: add %pC{,n,r} format specifiers for clocks")
Link: http://lkml.kernel.org/r/1527845302-12159-5-git-send-email-geert+renesas@glider.be
To: Jia-Ju Bai
To: Jonathan Corbet
To: Michael Turquette
To: Stephen Boyd
To: Zhang Rui
To: Eduardo Valentin
To: Eric Anholt
To: Stefan Wahren
To: Greg Kroah-Hartman
Cc: Sergey Senozhatsky
Cc: Petr Mladek
Cc: Linus Torvalds
Cc: Steven Rostedt
Cc: linux-doc@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Geert Uytterhoeven
Cc: stable@vger.kernel.org # 4.1+
Signed-off-by: Geert Uytterhoeven
Signed-off-by: Petr Mladek
24 Mar, 2018
1 commit
-
When debugging recent kernels, people will see '(ptrval)' but there
isn't much information as to what that means. Briefly describe why it's
there.Signed-off-by: Joel Stanley
Acked-by: Tobin C. Harding
Signed-off-by: Jonathan Corbet
02 Feb, 2018
1 commit
-
Pull printk updates from Petr Mladek:
- Add a console_msg_format command line option:
The value "default" keeps the old "[time stamp] text\n" format. The
value "syslog" allows to see the syslog-like "[timestamp] text" format.This feature was requested by people doing regression tests, for
example, 0day robot. They want to have both filtered and full logs
at hands.- Reduce the risk of softlockup:
Pass the console owner in a busy loop.
This is a new approach to the old problem. It was first proposed by
Steven Rostedt on Kernel Summit 2017. It marks a context in which
the console_lock owner calls console drivers and could not sleep.
On the other side, printk() callers could detect this state and use
a busy wait instead of a simple console_trylock(). Finally, the
console_lock owner checks if there is a busy waiter at the end of
the special context and eventually passes the console_lock to the
waiter.The hand-off works surprisingly well and helps in many situations.
Well, there is still a possibility of the softlockup, for example,
when the flood of messages stops and the last owner still has too
much to flush.There is increasing number of people having problems with
printk-related softlockups. We might eventually need to get better
solution. Anyway, this looks like a good start and promising
direction.- Do not allow to schedule in console_unlock() called from printk():
This reverts an older controversial commit. The reschedule helped
to avoid softlockups. But it also slowed down the console output.
This patch is obsoleted by the new console waiter logic described
above. In fact, the reschedule made the hand-off less effective.- Deprecate "%pf" and "%pF" format specifier:
It was needed on ia64, ppc64 and parisc64 to dereference function
descriptors and show the real function address. It is done
transparently by "%ps" and "pS" format specifier now.Sergey Senozhatsky found that all the function descriptors were in
a special elf section and could be easily detected.- Remove printk_symbol() API:
It has been obsoleted by "%pS" format specifier, and this change
helped to remove few continuous lines and a less intuitive old API.- Remove redundant memsets:
Sergey removed unnecessary memset when processing printk.devkmsg
command line option.* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (27 commits)
printk: drop redundant devkmsg_log_str memsets
printk: Never set console_may_schedule in console_trylock()
printk: Hide console waiter logic into helpers
printk: Add console owner and waiter logic to load balance console writes
kallsyms: remove print_symbol() function
checkpatch: add pF/pf deprecation warning
symbol lookup: introduce dereference_symbol_descriptor()
parisc64: Add .opd based function descriptor dereference
powerpc64: Add .opd based function descriptor dereference
ia64: Add .opd based function descriptor dereference
sections: split dereference_function_descriptor()
openrisc: Fix conflicting types for _exext and _stext
lib: do not use print_symbol()
irq debug: do not use print_symbol()
sysfs: do not use print_symbol()
drivers: do not use print_symbol()
x86: do not use print_symbol()
unicore32: do not use print_symbol()
sh: do not use print_symbol()
mn10300: do not use print_symbol()
...
22 Dec, 2017
1 commit
-
Documentation/printk-formats.txt is a candidate for conversion to
ReStructuredText format. Some effort has already been made to do this
conversion even thought the suffix is currently .txtChanges required to complete conversion
- Move printk-formats.txt to core-api/printk-formats.rst
- Add entry to Documentation/core-api/index.rst
- Remove entry from Documentation/00-INDEX
- Fix minor grammatical errors.
- Order heading adornments as suggested by rst docs.
- Use 'Passed by reference' uniformly.
- Update pointer documentation around %px specifier.
- Fix erroneous double backticks (to commas).
- Remove extraneous double backticks (suggested by Jonathan Corbet).
- Simplify documentation for kobject.Signed-off-by: Tobin C. Harding
[jc: downcased "kernel"]
Signed-off-by: Jonathan Corbet
