linux-stable.git/arch/xtensa/kernel, branch v5.15.78 Linux kernel stable tree xtensa: Fix refcount leak bug in time.c 2022-06-29T07:03:29+00:00 Liang He windhl@126.com 2022-06-17T12:44:32+00:00 0dcc1dd8a5dd9240639f1051dfaa2dffc9fbbde5 commit a0117dc956429f2ede17b323046e1968d1849150 upstream. In calibrate_ccount(), of_find_compatible_node() will return a node pointer with refcount incremented. We should use of_node_put() when it is not used anymore. Cc: stable@vger.kernel.org Signed-off-by: Liang He <windhl@126.com> Message-Id: <20220617124432.4049006-1-windhl@126.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a0117dc956429f2ede17b323046e1968d1849150 upstream.

In calibrate_ccount(), of_find_compatible_node() will return a node
pointer with refcount incremented. We should use of_node_put() when
it is not used anymore.

Cc: stable@vger.kernel.org
Signed-off-by: Liang He <windhl@126.com>
Message-Id: <20220617124432.4049006-1-windhl@126.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ptrace/xtensa: Replace PT_SINGLESTEP with TIF_SINGLESTEP 2022-06-09T08:22:29+00:00 Eric W. Biederman ebiederm@xmission.com 2022-04-26T21:45:37+00:00 7400a7e0a7ae1f1cd22250f0bfa1453f59a1d117 commit 4a3d2717d140401df7501a95e454180831a0c5af upstream. xtensa is the last user of the PT_SINGLESTEP flag. Changing tsk->ptrace in user_enable_single_step and user_disable_single_step without locking could potentiallly cause problems. So use a thread info flag instead of a flag in tsk->ptrace. Use TIF_SINGLESTEP that xtensa already had defined but unused. Remove the definitions of PT_SINGLESTEP and PT_BLOCKSTEP as they have no more users. Cc: stable@vger.kernel.org Acked-by: Max Filippov <jcmvbkbc@gmail.com> Tested-by: Kees Cook <keescook@chromium.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Link: https://lkml.kernel.org/r/20220505182645.497868-4-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 4a3d2717d140401df7501a95e454180831a0c5af upstream.

xtensa is the last user of the PT_SINGLESTEP flag.  Changing tsk->ptrace in
user_enable_single_step and user_disable_single_step without locking could
potentiallly cause problems.

So use a thread info flag instead of a flag in tsk->ptrace.  Use TIF_SINGLESTEP
that xtensa already had defined but unused.

Remove the definitions of PT_SINGLESTEP and PT_BLOCKSTEP as they have no more users.

Cc: stable@vger.kernel.org
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Tested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lkml.kernel.org/r/20220505182645.497868-4-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xtensa: fix a7 clobbering in coprocessor context load/store 2022-04-27T12:38:59+00:00 Max Filippov jcmvbkbc@gmail.com 2022-04-14T05:44:36+00:00 bac4cadeb71891d30df8d9a3bf884934a756edce commit 839769c35477d4acc2369e45000ca7b0b6af39a7 upstream. Fast coprocessor exception handler saves a3..a6, but coprocessor context load/store code uses a4..a7 as temporaries, potentially clobbering a7. 'Potentially' because coprocessor state load/store macros may not use all four temporary registers (and neither FPU nor HiFi macros do). Use a3..a6 as intended. Cc: stable@vger.kernel.org Fixes: c658eac628aa ("[XTENSA] Add support for configurable registers and coprocessors") Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 839769c35477d4acc2369e45000ca7b0b6af39a7 upstream.

Fast coprocessor exception handler saves a3..a6, but coprocessor context
load/store code uses a4..a7 as temporaries, potentially clobbering a7.
'Potentially' because coprocessor state load/store macros may not use
all four temporary registers (and neither FPU nor HiFi macros do).
Use a3..a6 as intended.

Cc: stable@vger.kernel.org
Fixes: c658eac628aa ("[XTENSA] Add support for configurable registers and coprocessors")
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xtensa: patch_text: Fixup last cpu should be master 2022-04-27T12:38:59+00:00 Guo Ren guoren@linux.alibaba.com 2022-04-07T07:33:22+00:00 91335ca9ebe79f2c85e183d9e632044f71836d02 commit ee69d4be8fd064cd08270b4808d2dfece3614ee0 upstream. These patch_text implementations are using stop_machine_cpuslocked infrastructure with atomic cpu_count. The original idea: When the master CPU patch_text, the others should wait for it. But current implementation is using the first CPU as master, which couldn't guarantee the remaining CPUs are waiting. This patch changes the last CPU as the master to solve the potential risk. Fixes: 64711f9a47d4 ("xtensa: implement jump_label support") Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> Reviewed-by: Max Filippov <jcmvbkbc@gmail.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: <stable@vger.kernel.org> Message-Id: <20220407073323.743224-4-guoren@kernel.org> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ee69d4be8fd064cd08270b4808d2dfece3614ee0 upstream.

These patch_text implementations are using stop_machine_cpuslocked
infrastructure with atomic cpu_count. The original idea: When the
master CPU patch_text, the others should wait for it. But current
implementation is using the first CPU as master, which couldn't
guarantee the remaining CPUs are waiting. This patch changes the
last CPU as the master to solve the potential risk.

Fixes: 64711f9a47d4 ("xtensa: implement jump_label support")
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: <stable@vger.kernel.org>
Message-Id: <20220407073323.743224-4-guoren@kernel.org>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xtensa: fix stop_machine_cpuslocked call in patch_text 2022-04-08T12:23:03+00:00 Max Filippov jcmvbkbc@gmail.com 2022-03-16T09:04:17+00:00 821907e8f516b01ea0c64f057b7d0a45ab242e17 commit f406f2d03e07afc199dd8cf501f361dde6be8a69 upstream. patch_text must invoke patch_text_stop_machine on all online CPUs, but it calls stop_machine_cpuslocked with NULL cpumask. As a result only one CPU runs patch_text_stop_machine potentially leaving stale icache entries on other CPUs. Fix that by calling stop_machine_cpuslocked with cpu_online_mask as the last argument. Cc: stable@vger.kernel.org Fixes: 64711f9a47d4 ("xtensa: implement jump_label support") Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f406f2d03e07afc199dd8cf501f361dde6be8a69 upstream.

patch_text must invoke patch_text_stop_machine on all online CPUs, but
it calls stop_machine_cpuslocked with NULL cpumask. As a result only one
CPU runs patch_text_stop_machine potentially leaving stale icache
entries on other CPUs. Fix that by calling stop_machine_cpuslocked with
cpu_online_mask as the last argument.

Cc: stable@vger.kernel.org
Fixes: 64711f9a47d4 ("xtensa: implement jump_label support")
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xtensa: call irqchip_init only when CONFIG_USE_OF is selected 2021-09-27T16:46:33+00:00 Max Filippov jcmvbkbc@gmail.com 2021-09-27T16:46:33+00:00 6489f8d0e1d93a3603d8dad8125797559e4cf2a2 During boot time kernel configured with OF=y but USE_OF=n displays the following warnings and hangs shortly after starting userspace: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at kernel/irq/irqdomain.c:695 irq_create_mapping_affinity+0x29/0xc0 irq_create_mapping_affinity(, 6) called with NULL domain CPU: 0 PID: 0 Comm: swapper Not tainted 5.15.0-rc3-00001-gd67ed2510d28 #30 Call Trace: __warn+0x69/0xc4 warn_slowpath_fmt+0x6c/0x94 irq_create_mapping_affinity+0x29/0xc0 local_timer_setup+0x40/0x88 time_init+0xb1/0xe8 start_kernel+0x31d/0x3f4 _startup+0x13b/0x13b ---[ end trace 1e6630e1c5eda35b ]--- ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at arch/xtensa/kernel/time.c:141 local_timer_setup+0x58/0x88 error: can't map timer irq CPU: 0 PID: 0 Comm: swapper Tainted: G W 5.15.0-rc3-00001-gd67ed2510d28 #30 Call Trace: __warn+0x69/0xc4 warn_slowpath_fmt+0x6c/0x94 local_timer_setup+0x58/0x88 time_init+0xb1/0xe8 start_kernel+0x31d/0x3f4 _startup+0x13b/0x13b ---[ end trace 1e6630e1c5eda35c ]--- Failed to request irq 0 (timer) Fix that by calling irqchip_init only when CONFIG_USE_OF is selected and calling legacy interrupt controller init otherwise. Fixes: da844a81779e ("xtensa: add device trees support") Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> 
During boot time kernel configured with OF=y but USE_OF=n displays the
following warnings and hangs shortly after starting userspace:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at kernel/irq/irqdomain.c:695 irq_create_mapping_affinity+0x29/0xc0
irq_create_mapping_affinity(, 6) called with NULL domain
CPU: 0 PID: 0 Comm: swapper Not tainted 5.15.0-rc3-00001-gd67ed2510d28 #30
Call Trace:
  __warn+0x69/0xc4
  warn_slowpath_fmt+0x6c/0x94
  irq_create_mapping_affinity+0x29/0xc0
  local_timer_setup+0x40/0x88
  time_init+0xb1/0xe8
  start_kernel+0x31d/0x3f4
  _startup+0x13b/0x13b
---[ end trace 1e6630e1c5eda35b ]---
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at arch/xtensa/kernel/time.c:141 local_timer_setup+0x58/0x88
error: can't map timer irq
CPU: 0 PID: 0 Comm: swapper Tainted: G        W         5.15.0-rc3-00001-gd67ed2510d28 #30
Call Trace:
  __warn+0x69/0xc4
  warn_slowpath_fmt+0x6c/0x94
  local_timer_setup+0x58/0x88
  time_init+0xb1/0xe8
  start_kernel+0x31d/0x3f4
  _startup+0x13b/0x13b
---[ end trace 1e6630e1c5eda35c ]---
Failed to request irq 0 (timer)

Fix that by calling irqchip_init only when CONFIG_USE_OF is selected and
calling legacy interrupt controller init otherwise.

Fixes: da844a81779e ("xtensa: add device trees support")
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
xtensa: use CONFIG_USE_OF instead of CONFIG_OF 2021-09-27T13:08:58+00:00 Randy Dunlap rdunlap@infradead.org 2021-09-25T03:29:51+00:00 d67ed2510d28a1eb33171010d35cf52178cfcbdd CONFIG_OF can be set by a randconfig or by a user -- without setting the early flattree option (OF_EARLY_FLATTREE). This causes build errors. However, if randconfig or a user sets USE_OF in the Xtensa config, the right kconfig symbols are set to fix the build. Fixes these build errors: ../arch/xtensa/kernel/setup.c:67:19: error: ‘__dtb_start’ undeclared here (not in a function); did you mean ‘dtb_start’? 67 | void *dtb_start = __dtb_start; | ^~~~~~~~~~~ ../arch/xtensa/kernel/setup.c: In function 'xtensa_dt_io_area': ../arch/xtensa/kernel/setup.c:201:14: error: implicit declaration of function 'of_flat_dt_is_compatible'; did you mean 'of_machine_is_compatible'? [-Werror=implicit-function-declaration] 201 | if (!of_flat_dt_is_compatible(node, "simple-bus")) ../arch/xtensa/kernel/setup.c:204:18: error: implicit declaration of function 'of_get_flat_dt_prop' [-Werror=implicit-function-declaration] 204 | ranges = of_get_flat_dt_prop(node, "ranges", &len); ../arch/xtensa/kernel/setup.c:204:16: error: assignment to 'const __be32 *' {aka 'const unsigned int *'} from 'int' makes pointer from integer without a cast [-Werror=int-conversion] 204 | ranges = of_get_flat_dt_prop(node, "ranges", &len); | ^ ../arch/xtensa/kernel/setup.c: In function 'early_init_devtree': ../arch/xtensa/kernel/setup.c:228:9: error: implicit declaration of function 'early_init_dt_scan'; did you mean 'early_init_devtree'? [-Werror=implicit-function-declaration] 228 | early_init_dt_scan(params); ../arch/xtensa/kernel/setup.c:229:9: error: implicit declaration of function 'of_scan_flat_dt' [-Werror=implicit-function-declaration] 229 | of_scan_flat_dt(xtensa_dt_io_area, NULL); xtensa-elf-ld: arch/xtensa/mm/mmu.o:(.text+0x0): undefined reference to `xtensa_kio_paddr' Fixes: da844a81779e ("xtensa: add device trees support") Fixes: 6cb971114f63 ("xtensa: remap io area defined in device tree") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> 
CONFIG_OF can be set by a randconfig or by a user -- without setting the
early flattree option (OF_EARLY_FLATTREE).  This causes build errors.
However, if randconfig or a user sets USE_OF in the Xtensa config,
the right kconfig symbols are set to fix the build.

Fixes these build errors:

../arch/xtensa/kernel/setup.c:67:19: error: ‘__dtb_start’ undeclared here (not in a function); did you mean ‘dtb_start’?
   67 | void *dtb_start = __dtb_start;
      |                   ^~~~~~~~~~~
../arch/xtensa/kernel/setup.c: In function 'xtensa_dt_io_area':
../arch/xtensa/kernel/setup.c:201:14: error: implicit declaration of function 'of_flat_dt_is_compatible'; did you mean 'of_machine_is_compatible'? [-Werror=implicit-function-declaration]
  201 |         if (!of_flat_dt_is_compatible(node, "simple-bus"))
../arch/xtensa/kernel/setup.c:204:18: error: implicit declaration of function 'of_get_flat_dt_prop' [-Werror=implicit-function-declaration]
  204 |         ranges = of_get_flat_dt_prop(node, "ranges", &len);
../arch/xtensa/kernel/setup.c:204:16: error: assignment to 'const __be32 *' {aka 'const unsigned int *'} from 'int' makes pointer from integer without a cast [-Werror=int-conversion]
  204 |         ranges = of_get_flat_dt_prop(node, "ranges", &len);
      |                ^
../arch/xtensa/kernel/setup.c: In function 'early_init_devtree':
../arch/xtensa/kernel/setup.c:228:9: error: implicit declaration of function 'early_init_dt_scan'; did you mean 'early_init_devtree'? [-Werror=implicit-function-declaration]
  228 |         early_init_dt_scan(params);
../arch/xtensa/kernel/setup.c:229:9: error: implicit declaration of function 'of_scan_flat_dt' [-Werror=implicit-function-declaration]
  229 |         of_scan_flat_dt(xtensa_dt_io_area, NULL);

xtensa-elf-ld: arch/xtensa/mm/mmu.o:(.text+0x0): undefined reference to `xtensa_kio_paddr'

Fixes: da844a81779e ("xtensa: add device trees support")
Fixes: 6cb971114f63 ("xtensa: remap io area defined in device tree")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Merge branch 'akpm' (patches from Andrew) 2021-09-03T17:08:28+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-09-03T17:08:28+00:00 14726903c835101cd8d0a703b609305094350d61 Merge misc updates from Andrew Morton: "173 patches. Subsystems affected by this series: ia64, ocfs2, block, and mm (debug, pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap, bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock, oom-kill, migration, ksm, percpu, vmstat, and madvise)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits) mm/madvise: add MADV_WILLNEED to process_madvise() mm/vmstat: remove unneeded return value mm/vmstat: simplify the array size calculation mm/vmstat: correct some wrong comments mm/percpu,c: remove obsolete comments of pcpu_chunk_populated() selftests: vm: add COW time test for KSM pages selftests: vm: add KSM merging time test mm: KSM: fix data type selftests: vm: add KSM merging across nodes test selftests: vm: add KSM zero page merging test selftests: vm: add KSM unmerge test selftests: vm: add KSM merge test mm/migrate: correct kernel-doc notation mm: wire up syscall process_mrelease mm: introduce process_mrelease system call memblock: make memblock_find_in_range method private mm/mempolicy.c: use in_task() in mempolicy_slab_node() mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies mm/mempolicy: advertise new MPOL_PREFERRED_MANY mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY ... 
Merge misc updates from Andrew Morton:
 "173 patches.

  Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
  pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
  bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
  hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
  oom-kill, migration, ksm, percpu, vmstat, and madvise)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits)
  mm/madvise: add MADV_WILLNEED to process_madvise()
  mm/vmstat: remove unneeded return value
  mm/vmstat: simplify the array size calculation
  mm/vmstat: correct some wrong comments
  mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
  selftests: vm: add COW time test for KSM pages
  selftests: vm: add KSM merging time test
  mm: KSM: fix data type
  selftests: vm: add KSM merging across nodes test
  selftests: vm: add KSM zero page merging test
  selftests: vm: add KSM unmerge test
  selftests: vm: add KSM merge test
  mm/migrate: correct kernel-doc notation
  mm: wire up syscall process_mrelease
  mm: introduce process_mrelease system call
  memblock: make memblock_find_in_range method private
  mm/mempolicy.c: use in_task() in mempolicy_slab_node()
  mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
  mm/mempolicy: advertise new MPOL_PREFERRED_MANY
  mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
  ...
mm: wire up syscall process_mrelease 2021-09-03T16:58:17+00:00 Suren Baghdasaryan surenb@google.com 2021-09-02T22:00:33+00:00 dce49103962840dd61423d7627748d6c558d58c5 Split off from prev patch in the series that implements the syscall. Link: https://lkml.kernel.org/r/20210809185259.405936-2-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Jan Engelhardt <jengelh@inai.de> Cc: Jann Horn <jannh@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Rik van Riel <riel@surriel.com> Cc: Roman Gushchin <guro@fb.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Tim Murray <timmurray@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Split off from prev patch in the series that implements the syscall.

Link: https://lkml.kernel.org/r/20210809185259.405936-2-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Jan Engelhardt <jengelh@inai.de>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tim Murray <timmurray@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge tag 'xtensa-20210902' of git://github.com/jcmvbkbc/linux-xtensa 2021-09-02T20:12:44+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-09-02T20:12:44+00:00 b5d6d2633c1b6b2b4599f658f8abe7eb1358cc77 Pull Xtensa updates from Max Filippov: - fix kconfig unmet dependency warning for HAVE_FUTEX_CMPXCHG - add fairness to handling IRQs of the same priority - fix pointer usage before NULL check in ISS console driver - build system cleanups * tag 'xtensa-20210902' of git://github.com/jcmvbkbc/linux-xtensa: xtensa: move core-y in arch/xtensa/Makefile to arch/xtensa/Kbuild xtensa: build platform directories unconditionally xtensa: do not build variants directory xtensa: remove unneeded exports xtensa: ISS: don't use string pointer before NULL check xtensa: add fairness to IRQ handling xtensa: fix kconfig unmet dependency warning for HAVE_FUTEX_CMPXCHG 
Pull Xtensa updates from Max Filippov:

 - fix kconfig unmet dependency warning for HAVE_FUTEX_CMPXCHG

 - add fairness to handling IRQs of the same priority

 - fix pointer usage before NULL check in ISS console driver

 - build system cleanups

* tag 'xtensa-20210902' of git://github.com/jcmvbkbc/linux-xtensa:
  xtensa: move core-y in arch/xtensa/Makefile to arch/xtensa/Kbuild
  xtensa: build platform directories unconditionally
  xtensa: do not build variants directory
  xtensa: remove unneeded exports
  xtensa: ISS: don't use string pointer before NULL check
  xtensa: add fairness to IRQ handling
  xtensa: fix kconfig unmet dependency warning for HAVE_FUTEX_CMPXCHG