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Max Filippov c21d040de6 highmem: fix checks in __kmap_local_sched_{in,out}
commit 66f133ceab upstream.

When CONFIG_DEBUG_KMAP_LOCAL is enabled __kmap_local_sched_{in,out} check
that even slots in the tsk->kmap_ctrl.pteval are unmapped.  The slots are
initialized with 0 value, but the check is done with pte_none.  0 pte
however does not necessarily mean that pte_none will return true.  e.g.
on xtensa it returns false, resulting in the following runtime warnings:

 WARNING: CPU: 0 PID: 101 at mm/highmem.c:627 __kmap_local_sched_out+0x51/0x108
 CPU: 0 PID: 101 Comm: touch Not tainted 5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13
 Call Trace:
   dump_stack+0xc/0x40
   __warn+0x8f/0x174
   warn_slowpath_fmt+0x48/0xac
   __kmap_local_sched_out+0x51/0x108
   __schedule+0x71a/0x9c4
   preempt_schedule_irq+0xa0/0xe0
   common_exception_return+0x5c/0x93
   do_wp_page+0x30e/0x330
   handle_mm_fault+0xa70/0xc3c
   do_page_fault+0x1d8/0x3c4
   common_exception+0x7f/0x7f

 WARNING: CPU: 0 PID: 101 at mm/highmem.c:664 __kmap_local_sched_in+0x50/0xe0
 CPU: 0 PID: 101 Comm: touch Tainted: G        W         5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13
 Call Trace:
   dump_stack+0xc/0x40
   __warn+0x8f/0x174
   warn_slowpath_fmt+0x48/0xac
   __kmap_local_sched_in+0x50/0xe0
   finish_task_switch$isra$0+0x1ce/0x2f8
   __schedule+0x86e/0x9c4
   preempt_schedule_irq+0xa0/0xe0
   common_exception_return+0x5c/0x93
   do_wp_page+0x30e/0x330
   handle_mm_fault+0xa70/0xc3c
   do_page_fault+0x1d8/0x3c4
   common_exception+0x7f/0x7f

Fix it by replacing !pte_none(pteval) with pte_val(pteval) != 0.

Link: https://lkml.kernel.org/r/20220403235159.3498065-1-jcmvbkbc@gmail.com
Fixes: 5fbda3ecd1 ("sched: highmem: Store local kmaps in task struct")
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-13 20:59:21 +02:00
Documentation docs: sysctl/kernel: add missing bit to panic_print 2022-04-08 14:24:16 +02:00
LICENSES
arch arm64: Add part number for Arm Cortex-A78AE 2022-04-13 20:59:20 +02:00
block block: Fix the maximum minor value is blk_alloc_ext_minor() 2022-04-08 14:24:11 +02:00
certs
crypto crypto: xts - Add softdep on ecb 2022-04-08 14:23:55 +02:00
drivers mmc: core: Fixup support for writeback-cache for eMMC and SD 2022-04-13 20:59:21 +02:00
fs io_uring: don't touch scm_fp_list after queueing skb 2022-04-13 20:59:20 +02:00
include rtc: mc146818-lib: fix RTC presence check 2022-04-13 20:59:14 +02:00
init init/main.c: return 1 from handled __setup() functions 2022-04-13 20:59:10 +02:00
ipc ipc/sem: do not sleep with a spin lock held 2022-02-08 18:34:03 +01:00
kernel swiotlb: Support aligned swiotlb buffers 2022-04-08 14:24:17 +02:00
lib lz4: fix LZ4_decompress_safe_partial read out of bound 2022-04-13 20:59:21 +02:00
mm highmem: fix checks in __kmap_local_sched_{in,out} 2022-04-13 20:59:21 +02:00
net SUNRPC: svc_tcp_sendmsg() should handle errors from xdr_alloc_bvec() 2022-04-13 20:59:20 +02:00
samples samples/bpf, xdpsock: Fix race when running for fix duration of time 2022-04-08 14:23:40 +02:00
scripts modpost: restore the warning message for missing symbol versions 2022-04-08 14:24:10 +02:00
security Fix incorrect type in assignment of ipv6 port for audit 2022-04-08 14:23:55 +02:00
sound ASoC: topology: Allow TLV control to be either read or write 2022-04-08 14:24:15 +02:00
tools perf session: Remap buf if there is no space for event 2022-04-13 20:59:20 +02:00
usr usr/include/Makefile: add linux/nfc.h to the compile-test coverage 2022-02-01 17:27:15 +01:00
virt KVM: Prevent module exit until all VMs are freed 2022-04-08 14:24:07 +02:00
.clang-format
.cocciconfig
.get_maintainer.ignore
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.mailmap
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MAINTAINERS MAINTAINERS: adjust file entry for of_net.c after movement 2022-03-08 19:12:53 +01:00
Makefile Linux 5.15.33 2022-04-08 14:24:18 +02:00
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