Re: [PATCH v9 4/7] extable: Add function to search only kernel exception table
Balbir Singh writes: > On 12/8/19 7:22 pm, Santosh Sivaraj wrote: >> Certain architecture specific operating modes (e.g., in powerpc machine >> check handler that is unable to access vmalloc memory), the >> search_exception_tables cannot be called because it also searches the >> module exception tables if entry is not found in the kernel exception >> table. >> >> Cc: Thomas Gleixner >> Cc: Ingo Molnar >> Cc: Nicholas Piggin >> Signed-off-by: Santosh Sivaraj >> Reviewed-by: Nicholas Piggin >> --- >> include/linux/extable.h | 2 ++ >> kernel/extable.c| 11 +-- >> 2 files changed, 11 insertions(+), 2 deletions(-) >> >> diff --git a/include/linux/extable.h b/include/linux/extable.h >> index 41c5b3a25f67..81ecfaa83ad3 100644 >> --- a/include/linux/extable.h >> +++ b/include/linux/extable.h >> @@ -19,6 +19,8 @@ void trim_init_extable(struct module *m); >> >> /* Given an address, look for it in the exception tables */ >> const struct exception_table_entry *search_exception_tables(unsigned long >> add); >> +const struct exception_table_entry * >> +search_kernel_exception_table(unsigned long addr); >> > > Can we find a better name search_kernel still sounds like all of the kernel. > Can we rename it to search_kernel_linear_map_extable? I thought search_kernel_exception_table and search_module_extables were non-ambiguous enough :-) But If you think name will be confusing, I can change that as suggested. Thanks, Santosh > > >> #ifdef CONFIG_MODULES >> /* For extable.c to search modules' exception tables. */ >> diff --git a/kernel/extable.c b/kernel/extable.c >> index e23cce6e6092..f6c9406eec7d 100644 >> --- a/kernel/extable.c >> +++ b/kernel/extable.c >> @@ -40,13 +40,20 @@ void __init sort_main_extable(void) >> } >> } >> >> +/* Given an address, look for it in the kernel exception table */ >> +const >> +struct exception_table_entry *search_kernel_exception_table(unsigned long >> addr) >> +{ >> +return search_extable(__start___ex_table, >> + __stop___ex_table - __start___ex_table, addr); >> +} >> + >> /* Given an address, look for it in the exception tables. */ >> const struct exception_table_entry *search_exception_tables(unsigned long >> addr) >> { >> const struct exception_table_entry *e; >> >> -e = search_extable(__start___ex_table, >> - __stop___ex_table - __start___ex_table, addr); >> +e = search_kernel_exception_table(addr); >> if (!e) >> e = search_module_extables(addr); >> return e; >> -- if (( RANDOM % 2 )); then ~/bin/cookie; else fortune -s; fi #cat ~/notes/quotes | sort -R | head -1 | cut -f2- -d " "
Re: [PATCH v9 4/7] extable: Add function to search only kernel exception table
On 12/8/19 7:22 pm, Santosh Sivaraj wrote: > Certain architecture specific operating modes (e.g., in powerpc machine > check handler that is unable to access vmalloc memory), the > search_exception_tables cannot be called because it also searches the > module exception tables if entry is not found in the kernel exception > table. > > Cc: Thomas Gleixner > Cc: Ingo Molnar > Cc: Nicholas Piggin > Signed-off-by: Santosh Sivaraj > Reviewed-by: Nicholas Piggin > --- > include/linux/extable.h | 2 ++ > kernel/extable.c| 11 +-- > 2 files changed, 11 insertions(+), 2 deletions(-) > > diff --git a/include/linux/extable.h b/include/linux/extable.h > index 41c5b3a25f67..81ecfaa83ad3 100644 > --- a/include/linux/extable.h > +++ b/include/linux/extable.h > @@ -19,6 +19,8 @@ void trim_init_extable(struct module *m); > > /* Given an address, look for it in the exception tables */ > const struct exception_table_entry *search_exception_tables(unsigned long > add); > +const struct exception_table_entry * > +search_kernel_exception_table(unsigned long addr); > Can we find a better name search_kernel still sounds like all of the kernel. Can we rename it to search_kernel_linear_map_extable? > #ifdef CONFIG_MODULES > /* For extable.c to search modules' exception tables. */ > diff --git a/kernel/extable.c b/kernel/extable.c > index e23cce6e6092..f6c9406eec7d 100644 > --- a/kernel/extable.c > +++ b/kernel/extable.c > @@ -40,13 +40,20 @@ void __init sort_main_extable(void) > } > } > > +/* Given an address, look for it in the kernel exception table */ > +const > +struct exception_table_entry *search_kernel_exception_table(unsigned long > addr) > +{ > + return search_extable(__start___ex_table, > + __stop___ex_table - __start___ex_table, addr); > +} > + > /* Given an address, look for it in the exception tables. */ > const struct exception_table_entry *search_exception_tables(unsigned long > addr) > { > const struct exception_table_entry *e; > > - e = search_extable(__start___ex_table, > -__stop___ex_table - __start___ex_table, addr); > + e = search_kernel_exception_table(addr); > if (!e) > e = search_module_extables(addr); > return e; >
[PATCH v9 4/7] extable: Add function to search only kernel exception table
Certain architecture specific operating modes (e.g., in powerpc machine check handler that is unable to access vmalloc memory), the search_exception_tables cannot be called because it also searches the module exception tables if entry is not found in the kernel exception table. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Nicholas Piggin Signed-off-by: Santosh Sivaraj Reviewed-by: Nicholas Piggin --- include/linux/extable.h | 2 ++ kernel/extable.c| 11 +-- 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/include/linux/extable.h b/include/linux/extable.h index 41c5b3a25f67..81ecfaa83ad3 100644 --- a/include/linux/extable.h +++ b/include/linux/extable.h @@ -19,6 +19,8 @@ void trim_init_extable(struct module *m); /* Given an address, look for it in the exception tables */ const struct exception_table_entry *search_exception_tables(unsigned long add); +const struct exception_table_entry * +search_kernel_exception_table(unsigned long addr); #ifdef CONFIG_MODULES /* For extable.c to search modules' exception tables. */ diff --git a/kernel/extable.c b/kernel/extable.c index e23cce6e6092..f6c9406eec7d 100644 --- a/kernel/extable.c +++ b/kernel/extable.c @@ -40,13 +40,20 @@ void __init sort_main_extable(void) } } +/* Given an address, look for it in the kernel exception table */ +const +struct exception_table_entry *search_kernel_exception_table(unsigned long addr) +{ + return search_extable(__start___ex_table, + __stop___ex_table - __start___ex_table, addr); +} + /* Given an address, look for it in the exception tables. */ const struct exception_table_entry *search_exception_tables(unsigned long addr) { const struct exception_table_entry *e; - e = search_extable(__start___ex_table, - __stop___ex_table - __start___ex_table, addr); + e = search_kernel_exception_table(addr); if (!e) e = search_module_extables(addr); return e; -- 2.21.0