Re: [PATCH v9 4/7] extable: Add function to search only kernel exception table
From: Balbir Singh <bsingharora@gmail.com>
Date: 2019-08-14 09:22:10
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On 12/8/19 7:22 pm, Santosh Sivaraj wrote:
quoted hunk ↗ jump to hunk
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 <redacted> Cc: Ingo Molnar <mingo@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Santosh Sivaraj <redacted> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> --- 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?
quoted hunk ↗ jump to hunk
#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;