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Linux kernel
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Pull x86 fixes from Borislav Petkov:
"I kinda knew while typing 'I hope this is the last batch of x86/urgent
updates' last week, Murphy was reading too and uttered 'Hold my
beer!'.
So here's more fixes... Thanks Murphy.
Anyway, three more x86/urgent fixes for 5.11 final. We should be
finally ready (famous last words). :-)
- An SGX use after free fix
- A fix for the fix to disable CET instrumentation generation for
kernel code. We forgot 32-bit, which we seem to do very often
nowadays
- A Xen PV fix to irqdomain init ordering"
* tag 'x86_urgent_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/pci: Create PCI/MSI irqdomain after x86_init.pci.arch_init()
x86/build: Disable CET instrumentation in the kernel for 32-bit too
x86/sgx: Maintain encl->refcount for each encl->mm_list entry
Pull clk fix from Stephen Boyd:
"One small fix for the Allwinner clk driver so that display clks figure
out the correct rate to use.
This fixes displays running 4k@60Hz and some other resolutions that
haven't been exercised and fully understood until now"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: sunxi-ng: mp: fix parent rate change flag check
Invoking x86_init.irqs.create_pci_msi_domain() before
x86_init.pci.arch_init() breaks XEN PV.
The XEN_PV specific pci.arch_init() function overrides the default
create_pci_msi_domain() which is obviously too late.
As a consequence the XEN PV PCI/MSI allocation goes through the native
path which runs out of vectors and causes malfunction.
Invoke it after x86_init.pci.arch_init().
Fixes: 6b15ffa07dc3 ("x86/irq: Initialize PCI/MSI domain at PCI init time")
Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87pn18djte.fsf@nanos.tec.linutronix.de
Pull SCSI fix from James Bottomley:
"One fix for scsi_debug that fixes a memory leak on module removal"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: scsi_debug: Fix a memory leak
CLK_SET_RATE_PARENT flag is checked on parent clock instead of current
one. Fix that.
Fixes: 3f790433c3cb ("clk: sunxi-ng: Adjust MP clock parent rate when allowed")
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Tested-by: Andre Heider <a.heider@gmail.com>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Link: https://lore.kernel.org/r/20210209175900.7092-2-jernej.skrabec@siol.net
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Commit
20bf2b378729 ("x86/build: Disable CET instrumentation in the kernel")
disabled CET instrumentation which gets added by default by the Ubuntu
gcc9 and 10 by default, but did that only for 64-bit builds. It would
still fail when building a 32-bit target. So disable CET for all x86
builds.
Fixes: 20bf2b378729 ("x86/build: Disable CET instrumentation in the kernel")
Reported-by: AC <achirvasub@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: AC <achirvasub@gmail.com>
Link: https://lkml.kernel.org/r/YCCIgMHkzh/xT4ex@arch-chirva.localdomain
Pull cgroup fixes from Tejun Heo:
"Two cgroup fixes:
- fix a NULL deref when trying to poll PSI in the root cgroup
- fix confusing controller parsing corner case when mounting cgroup
v1 hierarchies
And doc / maintainer file updates"
* 'for-5.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: update PSI file description in docs
cgroup: fix psi monitor for root cgroup
MAINTAINERS: Update my email address
MAINTAINERS: Remove stale URLs for cpuset
cgroup-v1: add disabled controller check in cgroup1_parse_param()
The sdebug_q_arr pointer must be freed when the module is unloaded.
$ cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff888e1cfb0000 (size 4096):
comm "modprobe", pid 165555, jiffies 4325987516 (age 685.194s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000458f4f5d>] 0xffffffffc06702d9
[<000000003edc4b1f>] do_one_initcall+0xe9/0x57d
[<00000000da7d518c>] do_init_module+0x1d1/0x6f0
[<000000009a6a9248>] load_module+0x36bd/0x4f50
[<00000000ddb0c3ce>] __do_sys_init_module+0x1db/0x260
[<000000009532db57>] do_syscall_64+0xa5/0x420
[<000000002916b13d>] entry_SYSCALL_64_after_hwframe+0x6a/0xdf
Fixes: 87c715dcde63 ("scsi: scsi_debug: Add per_host_store option")
Link: https://lore.kernel.org/r/20210208111734.34034-1-mlombard@redhat.com
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
pm_clk_suspend()/pm_clk_resume() are defined as NULL pointers rather than
empty inline stubs without CONFIG_PM:
drivers/clk/mmp/clk-audio.c:402:16: error: called object type 'void *' is not a function or function pointer
pm_clk_suspend(dev);
drivers/clk/mmp/clk-audio.c:411:15: error: called object type 'void *' is not a function or function pointer
pm_clk_resume(dev);
I tried redefining the helper functions, but that caused additional
problems. This is the simple solution of replacing the __maybe_unused
trick with an #ifdef.
Fixes: 725262d29139 ("clk: mmp2: Add audio clock controller driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210103135503.3668784-1-arnd@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
This has been shown in tests:
[ +0.000008] WARNING: CPU: 3 PID: 7620 at kernel/rcu/srcutree.c:374 cleanup_srcu_struct+0xed/0x100
This is essentially a use-after free, although SRCU notices it as
an SRCU cleanup in an invalid context.
== Background ==
SGX has a data structure (struct sgx_encl_mm) which keeps per-mm SGX
metadata. This is separate from struct sgx_encl because, in theory,
an enclave can be mapped from more than one mm. sgx_encl_mm includes
a pointer back to the sgx_encl.
This means that sgx_encl must have a longer lifetime than all of the
sgx_encl_mm's that point to it. That's usually the case: sgx_encl_mm
is freed only after the mmu_notifier is unregistered in sgx_release().
However, there's a race. If the process is exiting,
sgx_mmu_notifier_release() can be called in parallel with sgx_release()
instead of being called *by* it. The mmu_notifier path keeps encl_mm
alive past when sgx_encl can be freed. This inverts the lifetime rules
and means that sgx_mmu_notifier_release() can access a freed sgx_encl.
== Fix ==
Increase encl->refcount when encl_mm->encl is established. Release
this reference when encl_mm is freed. This ensures that encl outlives
encl_mm.
[ bp: Massage commit message. ]
Fixes: 1728ab54b4be ("x86/sgx: Add a page reclaimer")
Reported-by: Haitao Huang <haitao.huang@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20210207221401.29933-1-jarkko@kernel.org
Merge fixes from Andrew Morton:
"6 patches.
Subsystems affected by this patch series: mm/pagemap, scripts,
MAINTAINERS, and h8300"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
h8300: fix PREEMPTION build, TI_PRE_COUNT undefined
MAINTAINERS: add Andrey Konovalov to KASAN reviewers
MAINTAINERS: update Andrey Konovalov's email address
MAINTAINERS: update KASAN file list
scripts/recordmcount.pl: support big endian for ARCH sh
m68k: make __pfn_to_phys() and __phys_to_pfn() available for !MMU
Update PSI file description in cgroup-v2 docs to reflect the current
implementation.
tj: Changed cpu.pressure from read-only to read-write as suggested by
Johannes.
Signed-off-by: Odin Ugedal <odin@uged.al>
Acked-by: Dan Schatzberg <dschatzberg@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
In testing, in a configuration with Redfish and native NVMe multipath when
an EEH is injected, a kernel oops is being encountered:
(unreliable)
lpfc_nvme_ls_req+0x328/0x720 [lpfc]
__nvme_fc_send_ls_req.constprop.13+0x1d8/0x3d0 [nvme_fc]
nvme_fc_create_association+0x224/0xd10 [nvme_fc]
nvme_fc_reset_ctrl_work+0x110/0x154 [nvme_fc]
process_one_work+0x304/0x5d
the NBMe transport is issuing a Disconnect LS request, which the driver
receives and tries to post but the work queue used by the driver is already
being torn down by the eeh.
Fix by validating the validity of the work queue before proceeding with the
LS transmit.
Link: https://lore.kernel.org/r/20210127221601.84878-1-jsmart2021@gmail.com
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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