Michael Schmitz 8bf8d5dade m68k: Only force 030 bus error if PC not in exception table ... [ Upstream commit e36a82bebb ] __get_kernel_nofault() does copy data in supervisor mode when forcing a task backtrace log through /proc/sysrq_trigger. This is expected cause a bus error exception on e.g. NULL pointer dereferencing when logging a kernel task has no workqueue associated. This bus error ought to be ignored. Our 030 bus error handler is ill equipped to deal with this: Whenever ssw indicates a kernel mode access on a data fault, we don't even attempt to handle the fault and instead always send a SEGV signal (or panic). As a result, the check for exception handling at the fault PC (buried in send_sig_fault() which gets called from do_page_fault() eventually) is never used. In contrast, both 040 and 060 access error handlers do not care whether a fault happened on supervisor mode access, and will call do_page_fault() on those, ultimately honoring the exception table. Add a check in bus_error030 to call do_page_fault() in case we do have an entry for the fault PC in our exception table. I had attempted a fix for this earlier in 2019 that did rely on testing pagefault_disabled() (see link below) to achieve the same thing, but this patch should be more generic. Tested on 030 Atari Falcon. Reported-by: Eero Tamminen <oak@helsinkinet.fi> Link: https://lore.kernel.org/r/alpine.LNX.2.21.1904091023540.25@nippy.intranet Link: https://lore.kernel.org/r/63130691-1984-c423-c1f2-73bfd8d3dcd3@gmail.com Signed-off-by: Michael Schmitz <schmitzmic@gmail.com> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20230301021107.26307-1-schmitzmic@gmail.com Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-03-30 12:47:53 +02:00
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68000	m68k: Check syscall_trace_enter() return code	2023-03-10 09:39:49 +01:00
amiga	…
apollo	…
atari	…
bvme6000	…
coldfire	m68k: Check syscall_trace_enter() return code	2023-03-10 09:39:49 +01:00
configs	…
emu	…
fpsp040	…
hp300	…
ifpsp060	…
include	m68knommu: set ZERO_PAGE() to the allocated zeroed page	2022-06-14 18:36:15 +02:00
kernel	m68k: Only force 030 bus error if PC not in exception table	2023-03-30 12:47:53 +02:00
lib	…
mac	m68k: Remove set_fs()	2021-09-24 13:35:07 +02:00
math-emu	…
mm	exit: Add and use make_task_dead.	2023-02-01 08:27:20 +01:00
mvme16x	…
mvme147	…
q40	…
sun3	m68k: Remove set_fs()	2021-09-24 13:35:07 +02:00
sun3x	m68k: Remove set_fs()	2021-09-24 13:35:07 +02:00
tools/amiga	…
Kbuild	…
Kconfig	m68k: Remove set_fs()	2021-09-24 13:35:07 +02:00
Kconfig.bus	…
Kconfig.cpu	m68k: math-emu: Fix dependencies of math emulation support	2022-06-09 10:22:59 +02:00
Kconfig.debug	…
Kconfig.devices	m68k: /proc/hardware should depend on PROC_FS	2023-03-10 09:39:16 +01:00
Kconfig.machine	m68knommu: fix undefined reference to `_init_sp'	2022-06-14 18:36:15 +02:00
Makefile	…
install.sh	…