vmap_area does not exist on no-MMU, therefore the GDB scripts fail to
load:
Traceback (most recent call last):
File "<...>/vmlinux-gdb.py", line 51, in <module>
import linux.vmalloc
File "<...>/scripts/gdb/linux/vmalloc.py", line 14, in <module>
vmap_area_ptr_type = vmap_area_type.get_type().pointer()
^^^^^^^^^^^^^^^^^^^^^^^^^
File "<...>/scripts/gdb/linux/utils.py", line 28, in get_type
self._type = gdb.lookup_type(self._name)
^^^^^^^^^^^^^^^^^^^^^^^^^^^
gdb.error: No struct type named vmap_area.
To fix this, disable the command and add an informative error message if
CONFIG_MMU is not defined, following the example of lx-slabinfo.
Link: https://lkml.kernel.org/r/20231031202235.2655333-2-ben.wolsieffer@hefring.com
Fixes: 852622bf36 ("scripts/gdb/vmalloc: add vmallocinfo support")
Signed-off-by: Ben Wolsieffer <ben.wolsieffer@hefring.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
MOD_TEXT is only defined if CONFIG_MODULES=y which lead to loading failure
of the gdb scripts when kernel is built without CONFIG_MODULES=y:
Reading symbols from vmlinux...
Traceback (most recent call last):
File "/foo/vmlinux-gdb.py", line 25, in <module>
import linux.constants
File "/foo/scripts/gdb/linux/constants.py", line 14, in <module>
LX_MOD_TEXT = gdb.parse_and_eval("MOD_TEXT")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
gdb.error: No symbol "MOD_TEXT" in current context.
Add a conditional check on CONFIG_MODULES to fix this error.
Link: https://lkml.kernel.org/r/20231031134848.119391-1-da.gomez@samsung.com
Fixes: b4aff7513d ("scripts/gdb: use mem instead of core_layout to get the module address")
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Tested-by: Daniel Gomez <da.gomez@samsung.com>
Signed-off-by: Daniel Gomez <da.gomez@samsung.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
csr_sscratch CSR holds current task_struct address when hart is in user
space. Trap handler on entry spills csr_sscratch into "tp" (x2) register
and zeroes out csr_sscratch CSR. Trap handler on exit reloads "tp" with
expected user mode value and place current task_struct address again in
csr_sscratch CSR.
This patch assumes "tp" is pointing to task_struct. If value in
csr_sscratch is numerically greater than "tp" then it assumes csr_sscratch
is correct address of current task_struct. This logic holds when
- hart is in user space, "tp" will be less than csr_sscratch.
- hart is in kernel space but not in trap handler, "tp" will be more
than csr_sscratch (csr_sscratch being equal to 0).
- hart is executing trap handler
- "tp" is still pointing to user mode but csr_sscratch contains
ptr to task_struct. Thus numerically higher.
- "tp" is pointing to task_struct but csr_sscratch now contains
either 0 or numerically smaller value (transiently holds
user mode tp)
Link: https://lkml.kernel.org/r/20231026233837.612405-1-debug@rivosinc.com
Signed-off-by: Deepak Gupta <debug@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Tested-by: Hsieh-Tseng Shen <woodrow.shen@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Glenn Washburn <development@efficientek.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jeff Xie <xiehuan09@gmail.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Revert 11f956538c ("scripts/gdb/symbols: add specific ko module load
command") due to breakage identified by Johannes Berg in [1].
Fixes: 11f956538c ("scripts/gdb/symbols: add specific ko module load command")
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Closes: https://lkml.kernel.org/r/c44b748307a074d0c250002cdcfe209b8cce93c9.camel@sipsolutions.net [1]
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Qun-Wei Lin <qun-wei.lin@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add support for printing the backtrace of stackdepot handle.
This is the preparation patch for dumping page_owner,
slabtrace usage.
Link: https://lkml.kernel.org/r/20230808083020.22254-6-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Qun-Wei Lin <qun-wei.lin@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since we often use 'unsigned long', 'size_t', 'usigned int'
and 'struct page', we add these common types to utils.
Link: https://lkml.kernel.org/r/20230808083020.22254-4-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Qun-Wei Lin <qun-wei.lin@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When we get an text address from coredump and we cannot find
this address in vmlinux, it might located in kernel module.
We want to know which kernel module it located in.
This GDB scripts can help us to find the target kernel module.
(gdb) lx-getmod-by-textaddr 0xffff800002d305ac
0xffff800002d305ac is in kasan_test.ko
Link: https://lkml.kernel.org/r/20230808083020.22254-3-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Qun-Wei Lin <qun-wei.lin@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Add GDB memory helper commands", v2.
I've created some GDB commands I think useful when I debug some memory
issues and kernel module issue.
For memory issue, we would like to get slabinfo, slabtrace, page_owner and
vmallocinfo to debug the memory issues.
For module issue, we would like to query kernel module name when we get a
module text address and load module symbol by specific path.
Patch 1-2:
- Add kernel module related command.
Patch 3-5:
- Prepares for the memory-related command.
Patch 6-8:
- Add memory-related commands.
This patch (of 8):
Add lx-symbols <ko_path> command to support add specific
ko module.
Example output like below:
(gdb) lx-symbols mm/kasan/kasan_test.ko
loading @0xffff800002d30000: mm/kasan/kasan_test.ko
Link: https://lkml.kernel.org/r/20230808083020.22254-1-Kuan-Ying.Lee@mediatek.com
Link: https://lkml.kernel.org/r/20230808083020.22254-2-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Qun-Wei Lin <qun-wei.lin@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
'lsmod' shows total core layout size, so we need to sum up all the
sections in core layout in gdb scripts.
/ # lsmod
kasan_test 200704 0 - Live 0xffff80007f640000
Before patch:
(gdb) lx-lsmod
Address Module Size Used by
0xffff80007f640000 kasan_test 36864 0
After patch:
(gdb) lx-lsmod
Address Module Size Used by
0xffff80007f640000 kasan_test 200704 0
Link: https://lkml.kernel.org/r/20230710092852.31049-1-Kuan-Ying.Lee@mediatek.com
Fixes: b4aff7513d ("scripts/gdb: use mem instead of core_layout to get the module address")
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Qun-Wei Lin <qun-wei.lin@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
lx-symbols assumes that module's .text sections is located at
`module->mem[MOD_TEXT].base` and passes it to add-symbol-file command.
However, .text section follows after .plt section in modules built by LLVM
toolchain for arm64 target. Symbol addresses are skewed in GDB.
Fix this issue by using the address of .text section stored in
`module->sect_attrs`.
Link: https://lkml.kernel.org/r/20230801121052.2475183-1-koudai@google.com
Signed-off-by: Koudai Iwahori <koudai@google.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
--0000000000009a0c9905fd9173ad
Content-Transfer-Encoding: 8bit
After f15afbd34d ("fs: fix undefined behavior in bit shift for
SB_NOUSER") the constants were changed from plain integers which
LX_VALUE() can parse to constants using the BIT() macro which causes the
following:
Reading symbols from build/linux-custom/vmlinux...done.
Traceback (most recent call last):
File "/home/fainelli/work/buildroot/output/arm64/build/linux-custom/vmlinux-gdb.py", line 25, in <module>
import linux.constants
File "/home/fainelli/work/buildroot/output/arm64/build/linux-custom/scripts/gdb/linux/constants.py", line 5
LX_SB_RDONLY = ((((1UL))) << (0))
Use LX_GDBPARSED() which does not suffer from that issue.
f15afbd34d ("fs: fix undefined behavior in bit shift for SB_NOUSER")
Link: https://lkml.kernel.org/r/20230607221337.2781730-1-florian.fainelli@broadcom.com
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Cc: Hao Ge <gehao@kylinos.cn>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
- updates to scripts/gdb from Glenn Washburn
- kexec cleanups from Bjorn Helgaas
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Merge tag 'mm-nonmm-stable-2023-04-27-16-01' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
"Mainly singleton patches all over the place.
Series of note are:
- updates to scripts/gdb from Glenn Washburn
- kexec cleanups from Bjorn Helgaas"
* tag 'mm-nonmm-stable-2023-04-27-16-01' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (50 commits)
mailmap: add entries for Paul Mackerras
libgcc: add forward declarations for generic library routines
mailmap: add entry for Oleksandr
ocfs2: reduce ioctl stack usage
fs/proc: add Kthread flag to /proc/$pid/status
ia64: fix an addr to taddr in huge_pte_offset()
checkpatch: introduce proper bindings license check
epoll: rename global epmutex
scripts/gdb: add GDB convenience functions $lx_dentry_name() and $lx_i_dentry()
scripts/gdb: create linux/vfs.py for VFS related GDB helpers
uapi/linux/const.h: prefer ISO-friendly __typeof__
delayacct: track delays from IRQ/SOFTIRQ
scripts/gdb: timerlist: convert int chunks to str
scripts/gdb: print interrupts
scripts/gdb: raise error with reduced debugging information
scripts/gdb: add a Radix Tree Parser
lib/rbtree: use '+' instead of '|' for setting color.
proc/stat: remove arch_idle_time()
checkpatch: check for misuse of the link tags
checkpatch: allow Closes tags with links
...
$lx_dentry_name() generates a full VFS path from a given dentry pointer,
and $lx_i_dentry() returns the dentry pointer associated with the given
inode pointer, if there is one.
Link: https://lkml.kernel.org/r/c9a5ad8efbfbd2cc6559e082734eed7628f43a16.1677631565.git.development@efficientek.com
Signed-off-by: Glenn Washburn <development@efficientek.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Antonio Borneo <antonio.borneo@foss.st.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "GDB VFS utils".
I've created a couple GDB convenience functions that I found useful when
debugging some VFS issues and figure others might find them useful. For
instance, they are useful in setting conditional breakpoints on VFS
functions where you only care if the dentry path is a certain value. I
took the opportunity to create a new "vfs" python module to give VFS
related utilities a home.
This patch (of 2):
This will allow for more VFS specific GDB helpers to be collected in one
place. Move utils.dentry_name into the vfs modules. Also a local
variable in proc.py was changed from vfs to mnt to prevent a naming
collision with the new vfs module.
[akpm@linux-foundation.org: add SPDX-License-Identifier]
Link: https://lkml.kernel.org/r/cover.1677631565.git.development@efficientek.com
Link: https://lkml.kernel.org/r/7bba4c065a8c2c47f1fc5b03a7278005b04db251.1677631565.git.development@efficientek.com
Signed-off-by: Glenn Washburn <development@efficientek.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Antonio Borneo <antonio.borneo@foss.st.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
join() expects strings but integers are given.
Convert chunks list to strings before passing it to join()
Link: https://lkml.kernel.org/r/20230406221217.1585486-4-f.fainelli@gmail.com
Signed-off-by: Amjad Ouled-Ameur <aouledameur@baylibre.com>
Signed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If CONFIG_DEBUG_INFO_REDUCED is enabled in the kernel configuration, we
will typically not be able to load vmlinux-gdb.py and will fail with:
Traceback (most recent call last):
File "/home/fainelli/work/buildroot/output/arm64/build/linux-custom/vmlinux-gdb.py", line 25, in <module>
import linux.utils
File "/home/fainelli/work/buildroot/output/arm64/build/linux-custom/scripts/gdb/linux/utils.py", line 131, in <module>
atomic_long_counter_offset = atomic_long_type.get_type()['counter'].bitpos
KeyError: 'counter'
Rather be left wondering what is happening only to find out that reduced
debug information is the cause, raise an eror. This was not typically a
problem until e3c8d33e0d ("scripts/gdb: fix 'lx-dmesg' on 32 bits arch")
but it has since then.
Link: https://lkml.kernel.org/r/20230406215252.1580538-1-f.fainelli@gmail.com
Fixes: e3c8d33e0d ("scripts/gdb: fix 'lx-dmesg' on 32 bits arch")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Antonio Borneo <antonio.borneo@foss.st.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Linux makes use of the Radix Tree data structure to store pointers indexed
by integer values. This structure is utilised across many structures in
the kernel including the IRQ descriptor tables, and several filesystems.
This module provides a method to lookup values from a structure given its
head node.
Usage:
The function lx_radix_tree_lookup, must be given a symbol of type struct
radix_tree_root, and an index into that tree.
The object returned is a generic integer value, and must be cast correctly
to the type based on the storage in the data structure.
For example, to print the irq descriptor in the sparse irq_desc_tree at
index 18, try the following:
(gdb) print (struct irq_desc)$lx_radix_tree_lookup(irq_desc_tree, 18)
This script previously existed under commit
e127a73d41 ("scripts/gdb: add a Radix Tree
Parser") and was later reverted with
b447e02548a3304c47b78b5e2d75a4312a8f17e1i (Revert "scripts/gdb: add a
Radix Tree Parser").
This version expects the XArray based radix tree implementation and has
been verified using QEMU/x86 on Linux 6.3-rc5.
[f.fainelli@gmail.com: revive and update for xarray implementation]
[f.fainelli@gmail.com: guard against a NULL node in the while loop]
Link: https://lkml.kernel.org/r/20230405222743.1191674-1-f.fainelli@gmail.com
Link: https://lkml.kernel.org/r/20230404214049.1016811-1-f.fainelli@gmail.com
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
HRTIMER_MAX_CLOCK_BASES is of enum type hrtimer_base_type. To print it as
an integer, HRTIMER_MAX_CLOCK_BASES should be converted first.
Link: https://lkml.kernel.org/r/TYCP286MB214640FF0E7F04AC3926A39EC6819@TYCP286MB2146.JPNP286.PROD.OUTLOOK.COM
Signed-off-by: Peng Liu <liupeng17@lenovo.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Below incompatibilities between Python2 and Python3 made lx-timerlist fail
to run under Python3.
o xrange() is replaced by range() in Python3
o bytes and str are different types in Python3
o the return value of Inferior.read_memory() is memoryview object in
Python3
akpm: cc stable so that older kernels are properly debuggable under newer
Python.
Link: https://lkml.kernel.org/r/TYCP286MB2146EE1180A4D5176CBA8AB2C6819@TYCP286MB2146.JPNP286.PROD.OUTLOOK.COM
Signed-off-by: Peng Liu <liupeng17@lenovo.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
commit 511885d706 ("lib/timerqueue: Rely on rbtree semantics for next
timer") changed struct timerqueue_head, and so print_active_timers()
should be changed accordingly with its way to interpret the structure.
Link: https://lkml.kernel.org/r/TYCP286MB21463BD277330B26DDC18903C6819@TYCP286MB2146.JPNP286.PROD.OUTLOOK.COM
Signed-off-by: Peng Liu <liupeng17@lenovo.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
commit ac3b432839 ("module: replace module_layout with module_memory")
changed the struct module data structure from module_layout to
module_memory. The core_layout member which is used while loading
modules are not available anymore leading to the following error while
running gdb:
(gdb) lx-symbols
loading vmlinux
Python Exception <class 'gdb.error'>: There is no member named core_layout.
Error occurred in Python: There is no member named core_layout.
Replace core_layout with its new counterpart mem[MOD_TEXT].
Fixes: ac3b432839 ("module: replace module_layout with module_memory")
Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Avoid generating an exception if there are no generic power domain(s)
registered:
(gdb) lx-genpd-summary
domain status children
/device runtime status
----------------------------------------------------------------------
Python Exception <class 'gdb.error'>: No symbol "gpd_list" in current context.
Error occurred in Python: No symbol "gpd_list" in current context.
(gdb) quit
[f.fainelli@gmail.com: correctly invoke gdb_eval_or_none]
Link: https://lkml.kernel.org/r/20230327185746.3856407-1-f.fainelli@gmail.com
Link: https://lkml.kernel.org/r/20230323231659.3319941-1-f.fainelli@gmail.com
Fixes: 8207d4a88e ("scripts/gdb: add lx-genpd-summary command")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Leonard Crestez <leonard.crestez@nxp.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Avoid generating an exception if there are no clocks registered:
(gdb) lx-clk-summary
enable prepare protect
clock count count count rate
------------------------------------------------------------------------
Python Exception <class 'gdb.error'>: No symbol "clk_root_list" in
current context.
Error occurred in Python: No symbol "clk_root_list" in current context.
Link: https://lkml.kernel.org/r/20230323225246.3302977-1-f.fainelli@gmail.com
Fixes: d1e9710b63 ("scripts/gdb: initial clk support: lx-clk-summary")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Leonard Crestez <leonard.crestez@nxp.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
A running x86 UML kernel reports with architecture "i386:x86-64" as it is
a sub-architecture. However, a difference with bare-metal x86 kernels is
in how it manages tasks and the current task struct. To identify that the
inferior is a UML kernel and not bare-metal, check for the existence of
the UML specific symbol "cpu_tasks" which contains the current task
struct.
Link: https://lkml.kernel.org/r/b839d611e2906ccef2725c34d8e353fab35fe75e.1677469905.git.development@efficientek.com
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Anton Ivanov <anton.ivanov@kot-begemot.co.uk>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "scripts/gdb: Support getting current task struct in UML",
v3.
A running x86 UML kernel reports with architecture "i386:x86-64" as it is
a sub-architecture. However, a difference with bare-metal x86 kernels is
in how it manages tasks and the current task struct. To identify that the
inferior is a UML kernel and not bare-metal, check for the existence of
the UML specific symbol "cpu_tasks" which contains the current task
struct.
This patch (of 3):
There is an extra space in a couple blocks in get_current_task. Though
python does not care, let's make the spacing consistent. Also, format
better an if expression, removing unneeded parenthesis.
Link: https://lkml.kernel.org/r/cover.1677469905.git.development@efficientek.com
Link: https://lkml.kernel.org/r/2e117b82240de6893f27cb6507242ce455ed7b5b.1677469905.git.development@efficientek.com
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Anton Ivanov <anton.ivanov@kot-begemot.co.uk>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Most notable is a set of zlib changes from Mikhail Zaslonko which enhances
and fixes zlib's use of S390 hardware support: "lib/zlib: Set of s390
DFLTCC related patches for kernel zlib".
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Merge tag 'mm-nonmm-stable-2023-02-20-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
"There is no particular theme here - mainly quick hits all over the
tree.
Most notable is a set of zlib changes from Mikhail Zaslonko which
enhances and fixes zlib's use of S390 hardware support: 'lib/zlib: Set
of s390 DFLTCC related patches for kernel zlib'"
* tag 'mm-nonmm-stable-2023-02-20-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (55 commits)
Update CREDITS file entry for Jesper Juhl
sparc: allow PM configs for sparc32 COMPILE_TEST
hung_task: print message when hung_task_warnings gets down to zero.
arch/Kconfig: fix indentation
scripts/tags.sh: fix the Kconfig tags generation when using latest ctags
nilfs2: prevent WARNING in nilfs_dat_commit_end()
lib/zlib: remove redundation assignement of avail_in dfltcc_gdht()
lib/Kconfig.debug: do not enable DEBUG_PREEMPT by default
lib/zlib: DFLTCC always switch to software inflate for Z_PACKET_FLUSH option
lib/zlib: DFLTCC support inflate with small window
lib/zlib: Split deflate and inflate states for DFLTCC
lib/zlib: DFLTCC not writing header bits when avail_out == 0
lib/zlib: fix DFLTCC ignoring flush modes when avail_in == 0
lib/zlib: fix DFLTCC not flushing EOBS when creating raw streams
lib/zlib: implement switching between DFLTCC and software
lib/zlib: adjust offset calculation for dfltcc_state
nilfs2: replace WARN_ONs for invalid DAT metadata block requests
scripts/spelling.txt: add "exsits" pattern and fix typo instances
fs: gracefully handle ->get_block not mapping bh in __mpage_writepage
cramfs: Kconfig: fix spelling & punctuation
...
When printing the name of the current process, it will report an error:
(gdb) p $lx_current().comm Python Exception <class 'gdb.error'> No symbol
"current_task" in current context.: Error occurred in Python: No symbol
"current_task" in current context.
Because e57ef2ed97 ("x86: Put hot per CPU variables into a struct")
changed it.
Link: https://lkml.kernel.org/r/20230204090139.1789264-1-xiehuan09@gmail.com
Fixes: e57ef2ed97 ("x86: Put hot per CPU variables into a struct")
Signed-off-by: Jeff Xie <xiehuan09@gmail.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This command provides a way to traverse the entire page hierarchy by a
given virtual address on x86. In addition to qemu's commands info
tlb/info mem it provides the complete information about the paging
structure for an arbitrary virtual address. It supports 4KB/2MB/1GB and 5
level paging.
Here is an example output for 2MB success translation:
(gdb) translate-vm address
cr3:
cr3 binary data 0x1085be003
next entry physical address 0x1085be000
---
bit 3 page level write through False
bit 4 page level cache disabled False
level 4:
entry address 0xffff8881085be7f8
page entry binary data 0x800000010ac83067
next entry physical address 0x10ac83000
---
bit 0 entry present True
bit 1 read/write access allowed True
bit 2 user access allowed True
bit 3 page level write through False
bit 4 page level cache disabled False
bit 5 entry has been accessed True
bit 7 page size False
bit 11 restart to ordinary False
bit 63 execute disable True
level 3:
entry address 0xffff88810ac83a48
page entry binary data 0x101af7067
next entry physical address 0x101af7000
---
bit 0 entry present True
bit 1 read/write access allowed True
bit 2 user access allowed True
bit 3 page level write through False
bit 4 page level cache disabled False
bit 5 entry has been accessed True
bit 7 page size False
bit 11 restart to ordinary False
bit 63 execute disable False
level 2:
entry address 0xffff888101af7368
page entry binary data 0x80000001634008e7
page size 2MB
page physical address 0x163400000
---
bit 0 entry present True
bit 1 read/write access allowed True
bit 2 user access allowed True
bit 3 page level write through False
bit 4 page level cache disabled False
bit 5 entry has been accessed True
bit 7 page size True
bit 6 page dirty True
bit 8 global translation False
bit 11 restart to ordinary True
bit 12 pat False
bits (59, 62) protection key 0
bit 63 execute disable True
[dmitrii.bundin.a@gmail.com: add SPDX line, other tweaks]
Link: https://lkml.kernel.org/r/20230113175151.22278-1-dmitrii.bundin.a@gmail.com
[akpm@linux-foundation.org: s/physicall/physical/]
Link: https://lkml.kernel.org/r/20230102171014.31408-1-dmitrii.bundin.a@gmail.com
Signed-off-by: Dmitrii Bundin <dmitrii.bundin.a@gmail.com>
Acked by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
fatfs, autofs, squashfs, procfs, etc.
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Merge tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc updates from Andrew Morton:
"Updates to various subsystems which I help look after. lib, ocfs2,
fatfs, autofs, squashfs, procfs, etc. A relatively small amount of
material this time"
* tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits)
scripts/gdb: ensure the absolute path is generated on initial source
MAINTAINERS: kunit: add David Gow as a maintainer of KUnit
mailmap: add linux.dev alias for Brendan Higgins
mailmap: update Kirill's email
profile: setup_profiling_timer() is moslty not implemented
ocfs2: fix a typo in a comment
ocfs2: use the bitmap API to simplify code
ocfs2: remove some useless functions
lib/mpi: fix typo 'the the' in comment
proc: add some (hopefully) insightful comments
bdi: remove enum wb_congested_state
kernel/hung_task: fix address space of proc_dohung_task_timeout_secs
lib/lzo/lzo1x_compress.c: replace ternary operator with min() and min_t()
squashfs: support reading fragments in readahead call
squashfs: implement readahead
squashfs: always build "file direct" version of page actor
Revert "squashfs: provide backing_dev_info in order to disable read-ahead"
fs/ocfs2: Fix spelling typo in comment
ia64: old_rr4 added under CONFIG_HUGETLB_PAGE
proc: fix test for "vsyscall=xonly" boot option
...
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Merge tag 'printk-for-5.20-sane' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- Allow reading kernel log in gdb even on 32 bits systems
- More granular check of the buffer usage in printf selftest
- Clang warning fix
* tag 'printk-for-5.20-sane' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
lib/test_printf.c: fix clang -Wformat warnings
scripts/gdb: fix 'lx-dmesg' on 32 bits arch
lib/test_printf.c: split write-beyond-buffer check in two
Post 'make scripts_gdb' a symbolic link to scripts/gdb/vmlinux-gdb.py is
created. Currently 'os.path.dirname(__file__)' does not generate the
absolute path to scripts/gdb resulting in the following:
(gdb) source vmlinux-gdb.py
Traceback (most recent call last):
File "scripts/gdb/vmlinux-gdb.py", line 25, in <module>
import linux.utils
ModuleNotFoundError: No module named 'linux'
This patch ensures that the absolute path to scripts/gdb in relation to
the given file is generated so each module can be located accordingly.
Link: https://lkml.kernel.org/r/20220712110248.1404125-1-atomlin@redhat.com
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently the command 'lx-symbols' in gdb exits with the error`Function
"do_init_module" not defined in "kernel/module.c"`. This occurs because
the file kernel/module.c was moved to kernel/module/main.c.
Fix this breakage by changing the path to "kernel/module/main.c" in
LoadModuleBreakpoint.
Signed-off-by: Khalid Masum <khalid.masum.92@gmail.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Fixes: cfc1d27789 ("module: Move all into module/")
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The type atomic_long_t can have size 4 or 8 bytes, depending on
CONFIG_64BIT; it's only content, the field 'counter', is either an
int or a s64 value.
Current code incorrectly uses the fixed size utils.read_u64() to
read the field 'counter' inside atomic_long_t.
On 32 bits architectures reading the last element 'tail_id' of the
struct prb_desc_ring:
struct prb_desc_ring {
...
atomic_long_t tail_id;
};
causes the utils.read_u64() to access outside the boundary of the
struct and the gdb command 'lx-dmesg' exits with error:
Python Exception <class 'IndexError'>: index out of range
Error occurred in Python: index out of range
Query the really used atomic_long_t counter type size.
Link: https://lore.kernel.org/r/20220617143758.137307-1-antonio.borneo@foss.st.com
Fixes: e60768311a ("scripts/gdb: update for lockless printk ringbuffer")
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
[pmladek@suse.com: Query the really used atomic_long_t counter type size]
Tested-by: Antonio Borneo <antonio.borneo@foss.st.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220719122831.19890-1-pmladek@suse.com
MAGIC_START("IKCFG_ST") and MAGIC_END("IKCFG_ED") are moved out
from the kernel_config_data variable.
Thus, we parse kernel_config_data directly instead of considering
offset of MAGIC_START and MAGIC_END.
Fixes: 13610aa908 ("kernel/configs: use .incbin directive to embed config_data.gz")
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
For the gdb command lx-dmesg, the entire descriptor, info, and text
data regions are read into memory before printing any records. For
large kernel log buffers, this not only causes a huge delay before
seeing any records, but it may also lead to python errors of too
much memory allocation.
Rather than reading in all these regions in advance, read them as
needed and only read the regions for the particular record that is
being printed.
The gdb macro "dmesg" in Documentation/admin-guide/kdump/gdbmacros.txt
already prints out the kernel log buffer like this.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/874k79c3a9.fsf@jogness.linutronix.de
This is related to two previous changes. Commit dfe4529ee4
("scripts/gdb: find vmlinux where it was before") and commit da036ae147
("scripts/gdb: handle split debug").
Although Chrome OS has been using the debug suffix for modules for a
while, it has just recently started using it for vmlinux as well. That
means we've now got to improve the detection of "vmlinux" to also handle
that it might end with ".debug".
Link: https://lkml.kernel.org/r/20211028151120.v2.1.Ie6bd5a232f770acd8c9ffae487a02170bad3e963@changeid
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arm64 uses SP_EL0 to save the current task_struct address. While running
in EL0, SP_EL0 is clobbered by userspace. So if the upper bit is not 1
(not TTBR1), the current address is invalid. This patch checks the upper
bit of SP_EL0, if the upper bit is 1, lx_current() of arm64 will return
the derefrence of current task. Otherwise, lx_current() will tell users
they are running in userspace(EL0).
While arm64 is running in EL0, it is actually pointless to print current
task as the memory of kernel space is not accessible in EL0.
Link: https://lkml.kernel.org/r/20210314203444.15188-3-song.bao.hua@hisilicon.com
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "scripts/gdb: clarify the platforms supporting lx_current and add arm64 support", v2.
lx_current depends on per_cpu current_task variable which exists on x86
only. so it actually works on x86 only. the 1st patch documents this
clearly; the 2nd patch adds support for arm64.
This patch (of 2):
x86 is the only architecture which has per_cpu current_task:
arch$ git grep current_task | grep -i per_cpu
x86/include/asm/current.h:DECLARE_PER_CPU(struct task_struct *, current_task);
x86/kernel/cpu/common.c:DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned =
x86/kernel/cpu/common.c:EXPORT_PER_CPU_SYMBOL(current_task);
x86/kernel/cpu/common.c:DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task;
x86/kernel/cpu/common.c:EXPORT_PER_CPU_SYMBOL(current_task);
x86/kernel/smpboot.c: per_cpu(current_task, cpu) = idle;
On other architectures, lx_current() will lead to a python exception:
(gdb) p $lx_current().pid
Python Exception <class 'gdb.error'> No symbol "current_task" in current context.:
Error occurred in Python: No symbol "current_task" in current context.
To avoid more people struggling and wasting time in other architectures,
document it.
Link: https://lkml.kernel.org/r/20210314203444.15188-1-song.bao.hua@hisilicon.com
Link: https://lkml.kernel.org/r/20210314203444.15188-2-song.bao.hua@hisilicon.com
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If we store the relative path, the user might later cd to a different
directory, and that would break the automatic symbol resolving that
happens when a module is loaded into the target kernel. Fix this by
storing the abspath() of each path given, just like we already do for the
cwd (os.getcwd() is absolute.)
Link: https://lkml.kernel.org/r/20201217091747.bf4332cf2b35.I10ebbdb7e9b80ab1a5cddebf53d073be8232d656@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the list is uninitialized (next pointer is NULL), list_for_each gets
stuck in an infinite loop. Print a message and treat list as empty.
Link: https://lkml.kernel.org/r/4ae23bb1-c333-f669-da2d-fa35c4f49018@amazon.com
Signed-off-by: George Prekas <prekageo@amazon.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As commit d0e628cd81 ("kbuild: doc: clarify the difference between
extra-y and always-y") explained, extra-y should be used for listing
the prerequisites of vmlinux.
These targets are not related to vmlinux. always-y is a better fix.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
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Merge tag 'printk-for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
"The big new thing is the fully lockless ringbuffer implementation,
including the support for continuous lines. It will allow to store and
read messages in any situation wihtout the risk of deadlocks and
without the need of temporary per-CPU buffers.
The access is still serialized by logbuf_lock. It synchronizes few
more operations, for example, temporary buffer for formatting the
message, syslog and kmsg_dump operations. The lock removal is being
discussed and should be ready for the next release.
The continuous lines are handled exactly the same way as before to
avoid regressions in user space. It means that they are appended to
the last message when the caller is the same. Only the last message
can be extended.
The data ring includes plain text of the messages. Except for an
integer at the beginning of each message that points back to the
descriptor ring with other metadata.
The dictionary has to stay. journalctl uses it to filter the log. It
allows to show messages related to a given device. The dictionary
values are stored in the descriptor ring with the other metadata.
This is the first part of the printk rework as discussed at Plumbers
2019, see https://lore.kernel.org/r/87k1acz5rx.fsf@linutronix.de. The
next big step will be handling consoles by kthreads during the normal
system operation. It will require special handling of situations when
the kthreads could not get scheduled, for example, early boot,
suspend, panic.
Other changes:
- Add John Ogness as a reviewer for printk subsystem. He is author of
the rework and is familiar with the code and history.
- Fix locking in serial8250_do_startup() to prevent lockdep report.
- Few code cleanups"
* tag 'printk-for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: (27 commits)
printk: Use fallthrough pseudo-keyword
printk: reduce setup_text_buf size to LOG_LINE_MAX
printk: avoid and/or handle record truncation
printk: remove dict ring
printk: move dictionary keys to dev_printk_info
printk: move printk_info into separate array
printk: reimplement log_cont using record extension
printk: ringbuffer: add finalization/extension support
printk: ringbuffer: change representation of states
printk: ringbuffer: clear initial reserved fields
printk: ringbuffer: add BLK_DATALESS() macro
printk: ringbuffer: relocate get_data()
printk: ringbuffer: avoid memcpy() on state_var
printk: ringbuffer: fix setting state in desc_read()
kernel.h: Move oops_in_progress to printk.h
scripts/gdb: update for lockless printk ringbuffer
scripts/gdb: add utils.read_ulong()
docs: vmcoreinfo: add lockless printk ringbuffer vmcoreinfo
printk: reduce LOG_BUF_SHIFT range for H8300
printk: ringbuffer: support dataless records
...
Ben Wolsieffer