<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch/arm64/kernel/hw_breakpoint.c, branch v5.2-rc5</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>perf/arch/arm64: Implement hw_breakpoint_arch_parse()</title>
<updated>2018-06-26T07:07:56+00:00</updated>
<author>
<name>Frederic Weisbecker</name>
<email>frederic@kernel.org</email>
</author>
<published>2018-06-26T02:58:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8c449753a681517f0e6f877aad8539ac4c71757d'/>
<id>8c449753a681517f0e6f877aad8539ac4c71757d</id>
<content type='text'>
Migrate to the new API in order to remove arch_validate_hwbkpt_settings()
that clumsily mixes up architecture validation and commit.

Signed-off-by: Frederic Weisbecker &lt;frederic@kernel.org&gt;
Acked-by: Will Deacon &lt;will.deacon@arm.com&gt;
Acked-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@kernel.org&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Joel Fernandes &lt;joel.opensrc@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Rich Felker &lt;dalias@libc.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Yoshinori Sato &lt;ysato@users.sourceforge.jp&gt;
Link: http://lkml.kernel.org/r/1529981939-8231-7-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Migrate to the new API in order to remove arch_validate_hwbkpt_settings()
that clumsily mixes up architecture validation and commit.

Signed-off-by: Frederic Weisbecker &lt;frederic@kernel.org&gt;
Acked-by: Will Deacon &lt;will.deacon@arm.com&gt;
Acked-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@kernel.org&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Joel Fernandes &lt;joel.opensrc@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Rich Felker &lt;dalias@libc.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Yoshinori Sato &lt;ysato@users.sourceforge.jp&gt;
Link: http://lkml.kernel.org/r/1529981939-8231-7-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf/hw_breakpoint: Pass arch breakpoint struct to arch_check_bp_in_kernelspace()</title>
<updated>2018-06-26T07:07:54+00:00</updated>
<author>
<name>Frederic Weisbecker</name>
<email>frederic@kernel.org</email>
</author>
<published>2018-06-26T02:58:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8e983ff9ac02a8fb454ed09c2462bdb3617006a8'/>
<id>8e983ff9ac02a8fb454ed09c2462bdb3617006a8</id>
<content type='text'>
We can't pass the breakpoint directly on arch_check_bp_in_kernelspace()
anymore because its architecture internal datas (struct arch_hw_breakpoint)
are not yet filled by the time we call the function, and most
implementation need this backend to be up to date. So arrange the
function to take the probing struct instead.

Signed-off-by: Frederic Weisbecker &lt;frederic@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@kernel.org&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Joel Fernandes &lt;joel.opensrc@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Rich Felker &lt;dalias@libc.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Yoshinori Sato &lt;ysato@users.sourceforge.jp&gt;
Link: http://lkml.kernel.org/r/1529981939-8231-3-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We can't pass the breakpoint directly on arch_check_bp_in_kernelspace()
anymore because its architecture internal datas (struct arch_hw_breakpoint)
are not yet filled by the time we call the function, and most
implementation need this backend to be up to date. So arrange the
function to take the probing struct instead.

Signed-off-by: Frederic Weisbecker &lt;frederic@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@kernel.org&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Joel Fernandes &lt;joel.opensrc@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Rich Felker &lt;dalias@libc.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Yoshinori Sato &lt;ysato@users.sourceforge.jp&gt;
Link: http://lkml.kernel.org/r/1529981939-8231-3-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>compat: Move compat_timespec/ timeval to compat_time.h</title>
<updated>2018-04-19T11:29:54+00:00</updated>
<author>
<name>Deepa Dinamani</name>
<email>deepa.kernel@gmail.com</email>
</author>
<published>2018-03-14T04:03:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=0d55303c51a4f35f674617e415632d492b596c26'/>
<id>0d55303c51a4f35f674617e415632d492b596c26</id>
<content type='text'>
All the current architecture specific defines for these
are the same. Refactor these common defines to a common
header file.

The new common linux/compat_time.h is also useful as it
will eventually be used to hold all the defines that
are needed for compat time types that support non y2038
safe types. New architectures need not have to define these
new types as they will only use new y2038 safe syscalls.
This file can be deleted after y2038 when we stop supporting
non y2038 safe syscalls.

The patch also requires an operation similar to:

git grep "asm/compat\.h" | cut -d ":" -f 1 |  xargs -n 1 sed -i -e "s%asm/compat.h%linux/compat.h%g"

Cc: acme@kernel.org
Cc: benh@kernel.crashing.org
Cc: borntraeger@de.ibm.com
Cc: catalin.marinas@arm.com
Cc: cmetcalf@mellanox.com
Cc: cohuck@redhat.com
Cc: davem@davemloft.net
Cc: deller@gmx.de
Cc: devel@driverdev.osuosl.org
Cc: gerald.schaefer@de.ibm.com
Cc: gregkh@linuxfoundation.org
Cc: heiko.carstens@de.ibm.com
Cc: hoeppner@linux.vnet.ibm.com
Cc: hpa@zytor.com
Cc: jejb@parisc-linux.org
Cc: jwi@linux.vnet.ibm.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: mark.rutland@arm.com
Cc: mingo@redhat.com
Cc: mpe@ellerman.id.au
Cc: oberpar@linux.vnet.ibm.com
Cc: oprofile-list@lists.sf.net
Cc: paulus@samba.org
Cc: peterz@infradead.org
Cc: ralf@linux-mips.org
Cc: rostedt@goodmis.org
Cc: rric@kernel.org
Cc: schwidefsky@de.ibm.com
Cc: sebott@linux.vnet.ibm.com
Cc: sparclinux@vger.kernel.org
Cc: sth@linux.vnet.ibm.com
Cc: ubraun@linux.vnet.ibm.com
Cc: will.deacon@arm.com
Cc: x86@kernel.org
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Deepa Dinamani &lt;deepa.kernel@gmail.com&gt;
Acked-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: James Hogan &lt;jhogan@kernel.org&gt;
Acked-by: Helge Deller &lt;deller@gmx.de&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
All the current architecture specific defines for these
are the same. Refactor these common defines to a common
header file.

The new common linux/compat_time.h is also useful as it
will eventually be used to hold all the defines that
are needed for compat time types that support non y2038
safe types. New architectures need not have to define these
new types as they will only use new y2038 safe syscalls.
This file can be deleted after y2038 when we stop supporting
non y2038 safe syscalls.

The patch also requires an operation similar to:

git grep "asm/compat\.h" | cut -d ":" -f 1 |  xargs -n 1 sed -i -e "s%asm/compat.h%linux/compat.h%g"

Cc: acme@kernel.org
Cc: benh@kernel.crashing.org
Cc: borntraeger@de.ibm.com
Cc: catalin.marinas@arm.com
Cc: cmetcalf@mellanox.com
Cc: cohuck@redhat.com
Cc: davem@davemloft.net
Cc: deller@gmx.de
Cc: devel@driverdev.osuosl.org
Cc: gerald.schaefer@de.ibm.com
Cc: gregkh@linuxfoundation.org
Cc: heiko.carstens@de.ibm.com
Cc: hoeppner@linux.vnet.ibm.com
Cc: hpa@zytor.com
Cc: jejb@parisc-linux.org
Cc: jwi@linux.vnet.ibm.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: mark.rutland@arm.com
Cc: mingo@redhat.com
Cc: mpe@ellerman.id.au
Cc: oberpar@linux.vnet.ibm.com
Cc: oprofile-list@lists.sf.net
Cc: paulus@samba.org
Cc: peterz@infradead.org
Cc: ralf@linux-mips.org
Cc: rostedt@goodmis.org
Cc: rric@kernel.org
Cc: schwidefsky@de.ibm.com
Cc: sebott@linux.vnet.ibm.com
Cc: sparclinux@vger.kernel.org
Cc: sth@linux.vnet.ibm.com
Cc: ubraun@linux.vnet.ibm.com
Cc: will.deacon@arm.com
Cc: x86@kernel.org
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Deepa Dinamani &lt;deepa.kernel@gmail.com&gt;
Acked-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: James Hogan &lt;jhogan@kernel.org&gt;
Acked-by: Helge Deller &lt;deller@gmx.de&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: hw_breakpoint: Use linux/uaccess.h instead of asm/uaccess.h</title>
<updated>2017-12-12T11:53:26+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2017-12-12T11:53:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=0e17cada2a5b4dc847082e1db0e3f84599ffd436'/>
<id>0e17cada2a5b4dc847082e1db0e3f84599ffd436</id>
<content type='text'>
The only inclusion of asm/uaccess.h should be by linux/uaccess.h. All
other headers should use the latter.

Reported-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The only inclusion of asm/uaccess.h should be by linux/uaccess.h. All
other headers should use the latter.

Reported-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: hw_breakpoint: fix watchpoint matching for tagged pointers</title>
<updated>2017-05-09T16:26:40+00:00</updated>
<author>
<name>Kristina Martsenko</name>
<email>kristina.martsenko@arm.com</email>
</author>
<published>2017-05-03T15:37:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7dcd9dd8cebe9fa626af7e2358d03a37041a70fb'/>
<id>7dcd9dd8cebe9fa626af7e2358d03a37041a70fb</id>
<content type='text'>
When we take a watchpoint exception, the address that triggered the
watchpoint is found in FAR_EL1. We compare it to the address of each
configured watchpoint to see which one was hit.

The configured watchpoint addresses are untagged, while the address in
FAR_EL1 will have an address tag if the data access was done using a
tagged address. The tag needs to be removed to compare the address to
the watchpoints.

Currently we don't remove it, and as a result can report the wrong
watchpoint as being hit (specifically, always either the highest TTBR0
watchpoint or lowest TTBR1 watchpoint). This patch removes the tag.

Fixes: d50240a5f6ce ("arm64: mm: permit use of tagged pointers at EL0")
Cc: &lt;stable@vger.kernel.org&gt; # 3.12.x-
Acked-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Acked-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Kristina Martsenko &lt;kristina.martsenko@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When we take a watchpoint exception, the address that triggered the
watchpoint is found in FAR_EL1. We compare it to the address of each
configured watchpoint to see which one was hit.

The configured watchpoint addresses are untagged, while the address in
FAR_EL1 will have an address tag if the data access was done using a
tagged address. The tag needs to be removed to compare the address to
the watchpoints.

Currently we don't remove it, and as a result can report the wrong
watchpoint as being hit (specifically, always either the highest TTBR0
watchpoint or lowest TTBR1 watchpoint). This patch removes the tag.

Fixes: d50240a5f6ce ("arm64: mm: permit use of tagged pointers at EL0")
Cc: &lt;stable@vger.kernel.org&gt; # 3.12.x-
Acked-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Acked-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Kristina Martsenko &lt;kristina.martsenko@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cpu/hotplug: Cleanup state names</title>
<updated>2016-12-25T09:47:44+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2016-12-21T19:19:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=73c1b41e63f040e92669e61a02c7893933bfe743'/>
<id>73c1b41e63f040e92669e61a02c7893933bfe743</id>
<content type='text'>
When the state names got added a script was used to add the extra argument
to the calls. The script basically converted the state constant to a
string, but the cleanup to convert these strings into meaningful ones did
not happen.

Replace all the useless strings with 'subsys/xxx/yyy:state' strings which
are used in all the other places already.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sebastian Siewior &lt;bigeasy@linutronix.de&gt;
Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When the state names got added a script was used to add the extra argument
to the calls. The script basically converted the state constant to a
string, but the cleanup to convert these strings into meaningful ones did
not happen.

Replace all the useless strings with 'subsys/xxx/yyy:state' strings which
are used in all the other places already.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sebastian Siewior &lt;bigeasy@linutronix.de&gt;
Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: Allow hw watchpoint of length 3,5,6 and 7</title>
<updated>2016-11-18T17:26:14+00:00</updated>
<author>
<name>Pratyush Anand</name>
<email>panand@redhat.com</email>
</author>
<published>2016-11-14T14:02:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=0ddb8e0b784ba034f3096d5a54684d0d73155e2a'/>
<id>0ddb8e0b784ba034f3096d5a54684d0d73155e2a</id>
<content type='text'>
Since, arm64 can support all offset within a double word limit. Therefore,
now support other lengths within that range as well.

Signed-off-by: Pratyush Anand &lt;panand@redhat.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Since, arm64 can support all offset within a double word limit. Therefore,
now support other lengths within that range as well.

Signed-off-by: Pratyush Anand &lt;panand@redhat.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: hw_breakpoint: Handle inexact watchpoint addresses</title>
<updated>2016-11-18T17:25:50+00:00</updated>
<author>
<name>Pavel Labath</name>
<email>test.tberghammer@gmail.com</email>
</author>
<published>2016-11-14T14:02:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fdfeff0f9e3d9be2b68fa02566017ffc581ae17b'/>
<id>fdfeff0f9e3d9be2b68fa02566017ffc581ae17b</id>
<content type='text'>
Arm64 hardware does not always report a watchpoint hit address that
matches one of the watchpoints set. It can also report an address
"near" the watchpoint if a single instruction access both watched and
unwatched addresses. There is no straight-forward way, short of
disassembling the offending instruction, to map that address back to
the watchpoint.

Previously, when the hardware reported a watchpoint hit on an address
that did not match our watchpoint (this happens in case of instructions
which access large chunks of memory such as "stp") the process would
enter a loop where we would be continually resuming it (because we did
not recognise that watchpoint hit) and it would keep hitting the
watchpoint again and again. The tracing process would never get
notified of the watchpoint hit.

This commit fixes the problem by looking at the watchpoints near the
address reported by the hardware. If the address does not exactly match
one of the watchpoints we have set, it attributes the hit to the
nearest watchpoint we have.  This heuristic is a bit dodgy, but I don't
think we can do much more, given the hardware limitations.

Signed-off-by: Pavel Labath &lt;labath@google.com&gt;
[panand: reworked to rebase on his patches]
Signed-off-by: Pratyush Anand &lt;panand@redhat.com&gt;
[will: use __ffs instead of ffs - 1]
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Arm64 hardware does not always report a watchpoint hit address that
matches one of the watchpoints set. It can also report an address
"near" the watchpoint if a single instruction access both watched and
unwatched addresses. There is no straight-forward way, short of
disassembling the offending instruction, to map that address back to
the watchpoint.

Previously, when the hardware reported a watchpoint hit on an address
that did not match our watchpoint (this happens in case of instructions
which access large chunks of memory such as "stp") the process would
enter a loop where we would be continually resuming it (because we did
not recognise that watchpoint hit) and it would keep hitting the
watchpoint again and again. The tracing process would never get
notified of the watchpoint hit.

This commit fixes the problem by looking at the watchpoints near the
address reported by the hardware. If the address does not exactly match
one of the watchpoints we have set, it attributes the hit to the
nearest watchpoint we have.  This heuristic is a bit dodgy, but I don't
think we can do much more, given the hardware limitations.

Signed-off-by: Pavel Labath &lt;labath@google.com&gt;
[panand: reworked to rebase on his patches]
Signed-off-by: Pratyush Anand &lt;panand@redhat.com&gt;
[will: use __ffs instead of ffs - 1]
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: Allow hw watchpoint at varied offset from base address</title>
<updated>2016-11-18T17:23:17+00:00</updated>
<author>
<name>Pratyush Anand</name>
<email>panand@redhat.com</email>
</author>
<published>2016-11-14T14:02:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b08fb180bb8802d1c599beb1acd6a3b26163b4f6'/>
<id>b08fb180bb8802d1c599beb1acd6a3b26163b4f6</id>
<content type='text'>
ARM64 hardware supports watchpoint at any double word aligned address.
However, it can select any consecutive bytes from offset 0 to 7 from that
base address. For example, if base address is programmed as 0x420030 and
byte select is 0x1C, then access of 0x420032,0x420033 and 0x420034 will
generate a watchpoint exception.

Currently, we do not have such modularity. We can only program byte,
halfword, word and double word access exception from any base address.

This patch adds support to overcome above limitations.

Signed-off-by: Pratyush Anand &lt;panand@redhat.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
ARM64 hardware supports watchpoint at any double word aligned address.
However, it can select any consecutive bytes from offset 0 to 7 from that
base address. For example, if base address is programmed as 0x420030 and
byte select is 0x1C, then access of 0x420032,0x420033 and 0x420034 will
generate a watchpoint exception.

Currently, we do not have such modularity. We can only program byte,
halfword, word and double word access exception from any base address.

This patch adds support to overcome above limitations.

Signed-off-by: Pratyush Anand &lt;panand@redhat.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: hw_breakpoint: convert CPU hotplug notifier to new infrastructure</title>
<updated>2016-09-01T12:45:51+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2016-08-15T17:55:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d7a83d127a64fd91ef1ad39b7e2d78db36cf388b'/>
<id>d7a83d127a64fd91ef1ad39b7e2d78db36cf388b</id>
<content type='text'>
The arm64 hw_breakpoint implementation uses a CPU hotplug notifier to
reset the {break,watch}point registers when CPUs come online.

This patch converts the code to the new hotplug mechanism, whilst moving
the invocation earlier to remove the need to disable IRQs explicitly in
the driver (which could cause havok if we trip a watchpoint in an IRQ
handler whilst restoring the debug register state).

Cc: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Reviewed-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The arm64 hw_breakpoint implementation uses a CPU hotplug notifier to
reset the {break,watch}point registers when CPUs come online.

This patch converts the code to the new hotplug mechanism, whilst moving
the invocation earlier to remove the need to disable IRQs explicitly in
the driver (which could cause havok if we trip a watchpoint in an IRQ
handler whilst restoring the debug register state).

Cc: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Reviewed-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
