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* Merge https://github.com/TARKZiM/android_kernel_htc_msm8974 into HEADJulian Veit2022-08-191-0/+14
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| * Merge https://github.com/LineageOS/android_kernel_htc_msm8974 into lineage-18.1TARKZiM2021-08-183-3/+2
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| | * mm, oom: remove unnecessary exit_state checkDavid Rientjes2020-12-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The oom killer scans each process and determines whether it is eligible for oom kill or whether the oom killer should abort because of concurrent memory freeing. It will abort when an eligible process is found to have TIF_MEMDIE set, meaning it has already been oom killed and we're waiting for it to exit. Processes with task->mm == NULL should not be considered because they are either kthreads or have already detached their memory and killing them would not lead to memory freeing. That memory is only freed after exit_mm() has returned, however, and not when task->mm is first set to NULL. Clear TIF_MEMDIE after exit_mm()'s mmput() so that an oom killed process is no longer considered for oom kill, but only until exit_mm() has returned. This was fragile in the past because it relied on exit_notify() to be reached before no longer considering TIF_MEMDIE processes. Signed-off-by: David Rientjes <rientjes@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I1312e097463ce62c87030d3f3759e67ea8aade84
| | * mm: convert mm->nr_ptes to atomic_long_tKirill A. Shutemov2020-12-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With split page table lock for PMD level we can't hold mm->page_table_lock while updating nr_ptes. Let's convert it to atomic_long_t to avoid races. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Alex Thorlton <athorlton@sgi.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Jones <davej@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kees Cook <keescook@chromium.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Robin Holt <robinmholt@gmail.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I036141ce6b3a3bdbe6c61c1a9b717a67e1c99e3b
| | * oom: remove deprecated oom_adjDavidlohr Bueso2020-12-111-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The deprecated /proc/<pid>/oom_adj is scheduled for removal this month. Signed-off-by: Davidlohr Bueso <dave@gnu.org> Acked-by: David Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: Ie69cce40607ce68b6e4aed95496532b4b96b3789
| | * tcp: remove Appropriate Byte Count supportStephen Hemminger2020-11-051-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TCP Appropriate Byte Count was added by me, but later disabled. There is no point in maintaining it since it is a potential source of bugs and Linux already implements other better window protection heuristics. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Keith <javelinanddart@gmail.com>
| | * userns: Allow unprivileged users to create new namespacesEric W. Biederman2020-11-031-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | If an unprivileged user has the appropriate capabilities in their current user namespace allow the creation of new namespaces. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Change-Id: Ic3bdabc878944a7f3da0f3293d7163f051e65c34
| | * userns: Allow unprivileged use of setns.Eric W. Biederman2020-11-032-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Push the permission check from the core setns syscall into the setns install methods where the user namespace of the target namespace can be determined, and used in a ns_capable call. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Change-Id: I655fbd54531112ae7fe425a4055c2583a41deb78
| | * mm: Rename CGROUP_MEM_RES_CTLR to MEMCGArne Coucheron2020-11-031-1/+1
| | | | | | | | | | | | | | | | | | To match upstream. Change-Id: Ia280751e670ae0031b6756f346da4af4f74732e1
| * | kprobes: Fix to protect kick_kprobe_optimizer() by kprobe_mutexMasami Hiramatsu2020-08-101-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 1a0aa991a6274161c95a844c58cfb801d681eb59 ] In kprobe_optimizer() kick_kprobe_optimizer() is called without kprobe_mutex, but this can race with other caller which is protected by kprobe_mutex. To fix that, expand kprobe_mutex protected area to protect kick_kprobe_optimizer() call. Link: http://lkml.kernel.org/r/158927057586.27680.5036330063955940456.stgit@devnote2 Fixes: cd7ebe2298ff ("kprobes: Use text_poke_smp_batch for optimizing") Cc: Ingo Molnar <mingo@kernel.org> Cc: "Gustavo A . R . Silva" <gustavoars@kernel.org> Cc: Anders Roxell <anders.roxell@linaro.org> Cc: "Naveen N . Rao" <naveen.n.rao@linux.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ziqian SUN <zsun@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> Change-Id: I04b805e2c8a86c8b167d73bd6b29456529fb7a40
| * | tracing: Fix tracing_stat return values in error handling pathsLuis Henriques2020-08-101-4/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit afccc00f75bbbee4e4ae833a96c2d29a7259c693 upstream. tracing_stat_init() was always returning '0', even on the error paths. It now returns -ENODEV if tracing_init_dentry() fails or -ENOMEM if it fails to created the 'trace_stat' debugfs directory. Link: http://lkml.kernel.org/r/1410299381-20108-1-git-send-email-luis.henriques@canonical.com Fixes: ed6f1c996bfe4 ("tracing: Check return value of tracing_init_dentry()") Signed-off-by: Luis Henriques <luis.henriques@canonical.com> [ Pulled from the archeological digging of my INBOX ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Change-Id: I276a9eedfc826b13d489c2439bea1d3d0987a015
| * | tracing: Fix very unlikely race of registering two stat tracersSteven Rostedt (VMware)2020-08-101-10/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit dfb6cd1e654315168e36d947471bd2a0ccd834ae upstream. Looking through old emails in my INBOX, I came across a patch from Luis Henriques that attempted to fix a race of two stat tracers registering the same stat trace (extremely unlikely, as this is done in the kernel, and probably doesn't even exist). The submitted patch wasn't quite right as it needed to deal with clean up a bit better (if two stat tracers were the same, it would have the same files). But to make the code cleaner, all we needed to do is to keep the all_stat_sessions_mutex held for most of the registering function. Link: http://lkml.kernel.org/r/1410299375-20068-1-git-send-email-luis.henriques@canonical.com Fixes: 002bb86d8d42f ("tracing/ftrace: separate events tracing and stats tracing engine") Reported-by: Luis Henriques <luis.henriques@canonical.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Change-Id: I5b4fde6124794138daa374649b3fb1809de7c77f
| * | hrtimer: Catch illegal clockidsMarc Zyngier2020-08-101-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 9006a01829a50cfd6bbd4980910ed46e895e93d7 ] It is way too easy to take any random clockid and feed it to the hrtimer subsystem. At best, it gets mapped to a monotonic base, but it would be better to just catch illegal values as early as possible. This patch does exactly that, mapping illegal clockids to an illegal base index, and panicing when we detect the illegal condition. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Tomasz Nowicki <tn@semihalf.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> Link: http://lkml.kernel.org/r/1452879670-16133-3-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> Change-Id: I8a61d057fd7950dbaa654f02001cd50e6217f41b
| * | userns: Allow unprivileged users to create new namespacesEric W. Biederman2020-07-181-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | If an unprivileged user has the appropriate capabilities in their current user namespace allow the creation of new namespaces. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Change-Id: Ic3bdabc878944a7f3da0f3293d7163f051e65c34
| * | userns: Allow unprivileged use of setns.Eric W. Biederman2020-07-182-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Push the permission check from the core setns syscall into the setns install methods where the user namespace of the target namespace can be determined, and used in a ns_capable call. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Change-Id: I655fbd54531112ae7fe425a4055c2583a41deb78
| * | mm: Rename CGROUP_MEM_RES_CTLR to MEMCGArne Coucheron2020-07-181-1/+1
| | | | | | | | | | | | | | | | | | To match upstream. Change-Id: Ia280751e670ae0031b6756f346da4af4f74732e1
| * | add toggle for disabling newly added USB devicesDaniel Micay2020-06-291-0/+14
| |/ | | | | | | | | | | | | | | Based on the public grsecurity patches. Change-Id: I2cbea91b351cda7d098f4e1aa73dff1acbd23cce Signed-off-by: Daniel Micay <danielmicay@gmail.com> Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
* | tcp: remove Appropriate Byte Count supportStephen Hemminger2020-12-081-1/+0
| | | | | | | | | | | | | | | | | | | | | | TCP Appropriate Byte Count was added by me, but later disabled. There is no point in maintaining it since it is a potential source of bugs and Linux already implements other better window protection heuristics. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Keith <javelinanddart@gmail.com>
* | kprobes: Fix to protect kick_kprobe_optimizer() by kprobe_mutexMasami Hiramatsu2020-08-051-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 1a0aa991a6274161c95a844c58cfb801d681eb59 ] In kprobe_optimizer() kick_kprobe_optimizer() is called without kprobe_mutex, but this can race with other caller which is protected by kprobe_mutex. To fix that, expand kprobe_mutex protected area to protect kick_kprobe_optimizer() call. Link: http://lkml.kernel.org/r/158927057586.27680.5036330063955940456.stgit@devnote2 Fixes: cd7ebe2298ff ("kprobes: Use text_poke_smp_batch for optimizing") Cc: Ingo Molnar <mingo@kernel.org> Cc: "Gustavo A . R . Silva" <gustavoars@kernel.org> Cc: Anders Roxell <anders.roxell@linaro.org> Cc: "Naveen N . Rao" <naveen.n.rao@linux.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ziqian SUN <zsun@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> Change-Id: I04b805e2c8a86c8b167d73bd6b29456529fb7a40
* | tracing: Fix tracing_stat return values in error handling pathsLuis Henriques2020-06-111-4/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit afccc00f75bbbee4e4ae833a96c2d29a7259c693 upstream. tracing_stat_init() was always returning '0', even on the error paths. It now returns -ENODEV if tracing_init_dentry() fails or -ENOMEM if it fails to created the 'trace_stat' debugfs directory. Link: http://lkml.kernel.org/r/1410299381-20108-1-git-send-email-luis.henriques@canonical.com Fixes: ed6f1c996bfe4 ("tracing: Check return value of tracing_init_dentry()") Signed-off-by: Luis Henriques <luis.henriques@canonical.com> [ Pulled from the archeological digging of my INBOX ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Change-Id: I276a9eedfc826b13d489c2439bea1d3d0987a015
* | tracing: Fix very unlikely race of registering two stat tracersSteven Rostedt (VMware)2020-06-111-10/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit dfb6cd1e654315168e36d947471bd2a0ccd834ae upstream. Looking through old emails in my INBOX, I came across a patch from Luis Henriques that attempted to fix a race of two stat tracers registering the same stat trace (extremely unlikely, as this is done in the kernel, and probably doesn't even exist). The submitted patch wasn't quite right as it needed to deal with clean up a bit better (if two stat tracers were the same, it would have the same files). But to make the code cleaner, all we needed to do is to keep the all_stat_sessions_mutex held for most of the registering function. Link: http://lkml.kernel.org/r/1410299375-20068-1-git-send-email-luis.henriques@canonical.com Fixes: 002bb86d8d42f ("tracing/ftrace: separate events tracing and stats tracing engine") Reported-by: Luis Henriques <luis.henriques@canonical.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Change-Id: I5b4fde6124794138daa374649b3fb1809de7c77f
* | hrtimer: Catch illegal clockidsMarc Zyngier2020-06-111-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 9006a01829a50cfd6bbd4980910ed46e895e93d7 ] It is way too easy to take any random clockid and feed it to the hrtimer subsystem. At best, it gets mapped to a monotonic base, but it would be better to just catch illegal values as early as possible. This patch does exactly that, mapping illegal clockids to an illegal base index, and panicing when we detect the illegal condition. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Tomasz Nowicki <tn@semihalf.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> Link: http://lkml.kernel.org/r/1452879670-16133-3-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> Change-Id: I8a61d057fd7950dbaa654f02001cd50e6217f41b
* | prctl: adds PR_SET_TIMERSLACK_PID for setting timer slack of an arbitrary ↵Ruchi Kandoi2020-06-111-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | thread. Second argument is similar to PR_SET_TIMERSLACK, if non-zero then the slack is set to that value otherwise sets it to the default for the thread. Takes PID of the thread as the third argument. This allows power/performance management software to set timer slack for other threads according to its policy for the thread (such as when the thread is designated foreground vs. background activity) Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com> Change-Id: I24fe0a3dc0042384fb01f664c40e73f096e85abb
* | sched: Make some macros available to other parts of the kernelArne Coucheron2020-06-111-18/+0
| | | | | | | | | | | | Needed for the updated binder from 3.18 Change-Id: I1aa577c5c592ce49014fb49c2fb81410aafbb69f
* | Revert "prctl: adds PR_SET_TIMERSLACK_PID for setting timer slack of an ↵Julian Veit2020-06-111-39/+0
| | | | | | | | | | | | | | | | | | arbitrary thread." This reverts commit d608717175938cec9e049ffb06b146e4a16cad69. Change-Id: Ica5e0bbe94be1fd9995161dc1544d1cadfaadb87 Signed-off-by: Julian Veit <claymore1298@gmail.com>
* | prctl: adds PR_SET_TIMERSLACK_PID for setting timer slack of an arbitrary ↵Ruchi Kandoi2020-06-111-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | thread. Second argument is similar to PR_SET_TIMERSLACK, if non-zero then the slack is set to that value otherwise sets it to the default for the thread. Takes PID of the thread as the third argument. This allows power/performance management software to set timer slack for other threads according to its policy for the thread (such as when the thread is designated foreground vs. background activity) Change-Id: I744d451ff4e60dae69f38f53948ff36c51c14a3f Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
* | mm, thp: add VM_INIT_DEF_MASK and PRCTL_THP_DISABLEAlex Thorlton2020-06-112-3/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add VM_INIT_DEF_MASK, to allow us to set the default flags for VMs. It also adds a prctl control which allows us to set the THP disable bit in mm->def_flags so that VMs will pick up the setting as they are created. Signed-off-by: Alex Thorlton <athorlton@sgi.com> Suggested-by: Oleg Nesterov <oleg@redhat.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: David Rientjes <rientjes@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I0cb999093e3091ef9894137b2163f8a4291e4665 Signed-off-by: Julian Veit <claymore1298@gmail.com>
* | sys: Replace hardcoding of -20 and 19 with MIN_NICE and MAX_NICEDongsheng Yang2020-06-111-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Robin Holt <holt@sgi.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Kees Cook <keescook@chromium.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/0261f094b836f1acbcdf52e7166487c0c77323c8.1392103744.git.yangds.fnst@cn.fujitsu.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Change-Id: I61114cde6c5cc939fb8a1b7ff9198264068745ac
* | kernel/sys.c: sys_reboot(): fix malformed panic messageliguang2020-06-111-1/+1
| | | | | | | | | | | | | | | | | | | | If LINUX_REBOOT_CMD_HALT for reboot failed, the message "cannot halt" will stay on the same line with the next message, so append a '\n'. Signed-off-by: liguang <lig.fnst@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: Ie12c31f4ebaad8cc8abde9d198ca04db1abaaf7e
* | kernel/sys.c: make prctl(PR_SET_MM) generally availableAmnon Shiloh2020-06-111-8/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The purpose of this patch is to allow privileged processes to set their own per-memory memory-region fields: start_code, end_code, start_data, end_data, start_brk, brk, start_stack, arg_start, arg_end, env_start, env_end. This functionality is needed by any application or package that needs to reconstruct Linux processes, that is, to start them in any way other than by means of an "execve()" from an executable file. This includes: 1. Restoring processes from a checkpoint-file (by all potential user-level checkpointing packages, not only CRIU's). 2. Restarting processes on another node after process migration. 3. Starting duplicated copies of a running process (for reliability and high-availablity). 4. Starting a process from an executable format that is not supported by Linux, thus requiring a "manual execve" by a user-level utility. 5. Similarly, starting a process from a networked and/or crypted executable that, for confidentiality, licensing or other reasons, may not be written to the local file-systems. The code that does that was already included in the Linux kernel by the CRIU group, in the form of "prctl(PR_SET_MM)", but prior to this was enclosed within their private "#ifdef CONFIG_CHECKPOINT_RESTORE", which is normally disabled. The patch removes those ifdefs. Signed-off-by: Amnon Shiloh <u3557@miso.sublimeip.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I0334ede271acb3ec41d788839b3480c62963616e
* | poweroff: change orderly_poweroff() to use schedule_work()Oleg Nesterov2020-06-111-25/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | David said: Commit 6c0c0d4d1080 ("poweroff: fix bug in orderly_poweroff()") apparently fixes one bug in orderly_poweroff(), but introduces another. The comments on orderly_poweroff() claim it can be called from any context - and indeed we call it from interrupt context in arch/powerpc/platforms/pseries/ras.c for example. But since that commit this is no longer safe, since call_usermodehelper_fns() is not safe in interrupt context without the UMH_NO_WAIT option. orderly_poweroff() can be used from any context but UMH_WAIT_EXEC is sleepable. Move the "force" logic into __orderly_poweroff() and change orderly_poweroff() to use the global poweroff_work which simply calls __orderly_poweroff(). While at it, remove the unneeded "int argc" and change argv_split() to use GFP_KERNEL. We use the global "bool poweroff_force" to pass the argument, this can obviously affect the previous request if it is pending/running. So we only allow the "false => true" transition assuming that the pending "true" should succeed anyway. If schedule_work() fails after that we know that work->func() was not called yet, it must see the new value. This means that orderly_poweroff() becomes async even if we do not run the command and always succeeds, schedule_work() can only fail if the work is already pending. We can export __orderly_poweroff() and change the non-atomic callers which want the old semantics. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reported-by: David Gibson <david@gibson.dropbear.id.au> Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi> Cc: Feng Hong <hongfeng@marvell.com> Cc: Kees Cook <keescook@chromium.org> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I5a5915ecb907f894d03c41db37648ab55f82f0e4
* | usermodehelper: cleanup/fix __orderly_poweroff() && argv_free()Oleg Nesterov2020-06-111-8/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __orderly_poweroff() does argv_free() if call_usermodehelper_fns() returns -ENOMEM. As Lucas pointed out, this can be wrong if -ENOMEM was not triggered by the failing call_usermodehelper_setup(), in this case both __orderly_poweroff() and argv_cleanup() can do kfree(). Kill argv_cleanup() and change __orderly_poweroff() to call argv_free() unconditionally like do_coredump() does. This info->cleanup() is not needed (and wrong) since 6c0c0d4d "fix bug in orderly_poweroff() which did the UMH_NO_WAIT => UMH_WAIT_EXEC change, we can rely on the fact that CLONE_VFORK can't return until do_execve() succeeds/fails. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Lucas De Marchi <lucas.demarchi@profusion.mobi> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: hongfeng <hongfeng@marvell.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I97bbbbb98c389a732fb0253a7c7e725a12671316
* | sys_prctl(): coding-style cleanupAndrew Morton2020-06-111-132/+166
| | | | | | | | | | | | | | | | | | | | | | | | | | Remove a tabstop from the switch statement, in the usual fashion. A few instances of weirdwrapping were removed as a result. Cc: Chen Gang <gang.chen@asianux.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I29199257bb8f033f4d5bf68fecfabc35d54b4532 Signed-off-by: Julian Veit <claymore1298@gmail.com>
* | sys_prctl(): arg2 is unsigned long which is never < 0Chen Gang2020-06-111-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | arg2 will never < 0, for its type is 'unsigned long' Also, use the provided macros. Signed-off-by: Chen Gang <gang.chen@asianux.com> Reported-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I52b6aeb8ab43f66164f6809c5f6d1699aca5dd17
* | poweroff: fix bug in orderly_poweroff()hongfeng2020-06-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | orderly_poweroff is trying to poweroff platform in two steps: step 1: Call user space application to poweroff step 2: If user space poweroff fail, then do a force power off if force param is set. The bug here is, step 1 is always successful with param UMH_NO_WAIT, which obey the design goal of orderly_poweroff. We have two choices here: UMH_WAIT_EXEC which means wait for the exec, but not the process; UMH_WAIT_PROC which means wait for the process to complete. we need to trade off the two choices: If using UMH_WAIT_EXEC, there is potential issue comments by Serge E. Hallyn: The exec will have started, but may for whatever (very unlikely) reason fail. If using UMH_WAIT_PROC, there is potential issue comments by Eric W. Biederman: If the caller is not running in a kernel thread then we can easily get into a case where the user space caller will block waiting for us when we are waiting for the user space caller. Thanks for their excellent ideas, based on the above discussion, we finally choose UMH_WAIT_EXEC, which is much more safe, if the user application really fails, we just complain the application itself, it seems a better choice here. Signed-off-by: Feng Hong <hongfeng@marvell.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I24bbf3fc3d56d0dc8e85ca503003ab18a0b0a58c
* | switch prctl_set_mm_exe_file() to fget_light()Al Viro2020-06-111-4/+4
| | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Change-Id: I81105927ca8c7ffa3aabf3c2405e7a833093c53e
* | kernel/sys.c: avoid argv_free(NULL)Andrew Morton2020-06-111-19/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If argv_split() failed, the code will end up calling argv_free(NULL). Fix it up and clean things up a bit. Addresses Coverity report 703573. Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Kees Cook <keescook@chromium.org> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: WANG Cong <xiyou.wangcong@gmail.com> Cc: Alan Cox <alan@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: Ibd3b1a2405cdc51bae3d2fd61acb11e59c2badd3
* | prctl: remove redunant assignment of "error" to zeroSasikantha babu2020-06-111-11/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Just setting the "error" to error number is enough on failure and It doesn't require to set "error" variable to zero in each switch case, since it was already initialized with zero. And also removed return 0 in switch case with break statement Signed-off-by: Sasikantha babu <sasikanth.v19@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Serge E. Hallyn <serge@hallyn.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I26ef029c29d29a7a40ba53913cf8ec55d18879a6
* | c/r: prctl: less paranoid prctl_set_mm_exe_file()Konstantin Khlebnikov2020-06-111-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | "no other files mapped" requirement from my previous patch (c/r: prctl: update prctl_set_mm_exe_file() after mm->num_exe_file_vmas removal) is too paranoid, it forbids operation even if there mapped one shared-anon vma. Let's check that current mm->exe_file already unmapped, in this case exe_file symlink already outdated and its changing is reasonable. Plus, this patch fixes exit code in case operation success. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Reported-by: Cyrill Gorcunov <gorcunov@openvz.org> Tested-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Kees Cook <keescook@chromium.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Tejun Heo <tj@kernel.org> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I4a3cb1e888c184911a60057a71e806888768dab0
* | c/r: prctl: Move PR_GET_TID_ADDRESS to a proper placeCyrill Gorcunov2020-06-111-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During merging of PR_GET_TID_ADDRESS patch the code has been misplaced (it happened to appear under PR_MCE_KILL) in result noone can use this option. Fix it by moving code snippet to a proper place. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Andrey Vagin <avagin@openvz.org> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I536f134ab18782b3768c3d00cf48d7e51989aeee
* | c/r: prctl: drop VMA flags test on PR_SET_MM_ stack data assignmentCyrill Gorcunov2020-06-111-14/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit b76437579d13 ("procfs: mark thread stack correctly in proc/<pid>/maps") the stack allocated via clone() is marked in /proc/<pid>/maps as [stack:%d] thus it might be out of the former mm->start_stack/end_stack values (and even has some custom VMA flags set). So to be able to restore mm->start_stack/end_stack drop vma flags test, but still require the underlying VMA to exist. As always note this feature is under CONFIG_CHECKPOINT_RESTORE and requires CAP_SYS_RESOURCE to be granted. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Oleg Nesterov <oleg@redhat.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I0971daaa94a6bf40c59cc60543e441b89b976dcd
* | c/r: prctl: add ability to get clear_tid_addressCyrill Gorcunov2020-06-111-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Zero is written at clear_tid_address when the process exits. This functionality is used by pthread_join(). We already have sys_set_tid_address() to change this address for the current task but there is no way to obtain it from user space. Without the ability to find this address and dump it we can't restore pthread'ed apps which call pthread_join() once they have been restored. This patch introduces the PR_GET_TID_ADDRESS prctl option which allows the current process to obtain own clear_tid_address. This feature is available iif CONFIG_CHECKPOINT_RESTORE is set. [akpm@linux-foundation.org: fix prctl numbering] Signed-off-by: Andrew Vagin <avagin@openvz.org> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pedro Alves <palves@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Tejun Heo <tj@kernel.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: Ic52e71de7aac5eda1110fafa28a39b32e673ebba
* | c/r: prctl: add minimal address test to PR_SET_MMCyrill Gorcunov2020-06-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make sure the address being set is greater than mmap_min_addr (as suggested by Kees Cook). Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Kees Cook <keescook@chromium.org> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: Tejun Heo <tj@kernel.org> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I7ef6342a72e922a14d31688a053a472a7e5fb783
* | c/r: prctl: update prctl_set_mm_exe_file() after mm->num_exe_file_vmas removalKonstantin Khlebnikov2020-06-111-12/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A fix for commit b32dfe377102 ("c/r: prctl: add ability to set new mm_struct::exe_file"). After removing mm->num_exe_file_vmas kernel keeps mm->exe_file until final mmput(), it never becomes NULL while task is alive. We can check for other mapped files in mm instead of checking mm->num_exe_file_vmas, and mark mm with flag MMF_EXE_FILE_CHANGED in order to forbid second changing of mm->exe_file. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Kees Cook <keescook@chromium.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Tejun Heo <tj@kernel.org> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I2661bc84fffb55ad2857892fad2bb4d43b93e708
* | c/r: prctl: add ability to set new mm_struct::exe_fileCyrill Gorcunov2020-06-111-0/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we do restore we would like to have a way to setup a former mm_struct::exe_file so that /proc/pid/exe would point to the original executable file a process had at checkpoint time. For this the PR_SET_MM_EXE_FILE code is introduced. This option takes a file descriptor which will be set as a source for new /proc/$pid/exe symlink. Note it allows to change /proc/$pid/exe if there are no VM_EXECUTABLE vmas present for current process, simply because this feature is a special to C/R and mm::num_exe_file_vmas become meaningless after that. To minimize the amount of transition the /proc/pid/exe symlink might have, this feature is implemented in one-shot manner. Thus once changed the symlink can't be changed again. This should help sysadmins to monitor the symlinks over all process running in a system. In particular one could make a snapshot of processes and ring alarm if there unexpected changes of /proc/pid/exe's in a system. Note -- this feature is available iif CONFIG_CHECKPOINT_RESTORE is set and the caller must have CAP_SYS_RESOURCE capability granted, otherwise the request to change symlink will be rejected. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Kees Cook <keescook@chromium.org> Cc: Tejun Heo <tj@kernel.org> Cc: Matt Helsley <matthltc@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I4b5a9077203c784157abf61836db1c3f44a08ace
* | c/r: prctl: extend PR_SET_MM to set up more mm_struct entriesCyrill Gorcunov2020-06-111-51/+83
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During checkpoint we dump whole process memory to a file and the dump includes process stack memory. But among stack data itself, the stack carries additional parameters such as command line arguments, environment data and auxiliary vector. So when we do restore procedure and once we've restored stack data itself we need to setup mm_struct::arg_start/end, env_start/end, so restored process would be able to find command line arguments and environment data it had at checkpoint time. The same applies to auxiliary vector. For this reason additional PR_SET_MM_(ARG_START | ARG_END | ENV_START | ENV_END | AUXV) codes are introduced. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Kees Cook <keescook@chromium.org> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Vagin <avagin@openvz.org> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I3483d0ef6d525fd48f68b9dd4db60266cfb4eddc
* | kmod: convert two call sites to call_usermodehelper_fns()Boaz Harrosh2020-06-071-11/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Both kernel/sys.c && security/keys/request_key.c where inlining the exact same code as call_usermodehelper_fns(); So simply convert these sites to directly use call_usermodehelper_fns(). Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I8395103a2a07dc5790e216182c717a6269f63322
* | timer: convert timer_slack_ns from unsigned long to u64John Stultz2020-06-073-7/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patchset introduces a /proc/<pid>/timerslack_ns interface which would allow controlling processes to be able to set the timerslack value on other processes in order to save power by avoiding wakeups (Something Android currently does via out-of-tree patches). The first patch tries to fix the internal timer_slack_ns usage which was defined as a long, which limits the slack range to ~4 seconds on 32bit systems. It converts it to a u64, which provides the same basically unlimited slack (500 years) on both 32bit and 64bit machines. The second patch introduces the /proc/<pid>/timerslack_ns interface which allows the full 64bit slack range for a task to be read or set on both 32bit and 64bit machines. With these two patches, on a 32bit machine, after setting the slack on bash to 10 seconds: $ time sleep 1 real 0m10.747s user 0m0.001s sys 0m0.005s The first patch is a little ugly, since I had to chase the slack delta arguments through a number of functions converting them to u64s. Let me know if it makes sense to break that up more or not. Other than that things are fairly straightforward. This patch (of 2): The timer_slack_ns value in the task struct is currently a unsigned long. This means that on 32bit applications, the maximum slack is just over 4 seconds. However, on 64bit machines, its much much larger (~500 years). This disparity could make application development a little (as well as the default_slack) to a u64. This means both 32bit and 64bit systems have the same effective internal slack range. Now the existing ABI via PR_GET_TIMERSLACK and PR_SET_TIMERSLACK specify the interface as a unsigned long, so we preserve that limitation on 32bit systems, where SET_TIMERSLACK can only set the slack to a unsigned long value, and GET_TIMERSLACK will return ULONG_MAX if the slack is actually larger then what can be stored by an unsigned long. This patch also modifies hrtimer functions which specified the slack delta as a unsigned long. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Oren Laadan <orenl@cellrox.com> Cc: Ruchi Kandoi <kandoiruchi@google.com> Cc: Rom Lemarchand <romlem@android.com> Cc: Kees Cook <keescook@chromium.org> Cc: Android Kernel Team <kernel-team@android.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I566c7f1025959840a48262b604635bf880cfde4e
* | namespaces: Use task_lock and not rcu to protect nsproxyEric W. Biederman2020-06-072-14/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The synchronous syncrhonize_rcu in switch_task_namespaces makes setns a sufficiently expensive system call that people have complained. Upon inspect nsproxy no longer needs rcu protection for remote reads. remote reads are rare. So optimize for same process reads and write by switching using rask_lock instead. This yields a simpler to understand lock, and a faster setns system call. In particular this fixes a performance regression observed by Rafael David Tinoco <rafael.tinoco@canonical.com>. This is effectively a revert of Pavel Emelyanov's commit cf7b708c8d1d7a27736771bcf4c457b332b0f818 Make access to task's nsproxy lighter from 2007. The race this originialy fixed no longer exists as do_notify_parent uses task_active_pid_ns(parent) instead of parent->nsproxy. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Change-Id: I9fff45ba435ca15d34ce5e1ad4b9d28b6c165df7
* | mm, oom: remove unnecessary exit_state checkDavid Rientjes2020-06-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The oom killer scans each process and determines whether it is eligible for oom kill or whether the oom killer should abort because of concurrent memory freeing. It will abort when an eligible process is found to have TIF_MEMDIE set, meaning it has already been oom killed and we're waiting for it to exit. Processes with task->mm == NULL should not be considered because they are either kthreads or have already detached their memory and killing them would not lead to memory freeing. That memory is only freed after exit_mm() has returned, however, and not when task->mm is first set to NULL. Clear TIF_MEMDIE after exit_mm()'s mmput() so that an oom killed process is no longer considered for oom kill, but only until exit_mm() has returned. This was fragile in the past because it relied on exit_notify() to be reached before no longer considering TIF_MEMDIE processes. Signed-off-by: David Rientjes <rientjes@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I1312e097463ce62c87030d3f3759e67ea8aade84
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