From mboxrd@z Thu Jan 1 00:00:00 1970 From: tom.leiming@gmail.com (Ming Lei) Date: Mon, 28 Oct 2013 23:48:59 +0800 Subject: [PATCH] scripts/kallsyms: filter symbols not in kernel address space Message-ID: <1382975339-25831-1-git-send-email-tom.leiming@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org This patch uses CONFIG_PAGE_OFFSET to filter symbols which are not in kernel address space because these symbols are generally for generating code purpose and can't be run at kernel mode, so we needn't keep them in /proc/kallsyms. For example, on ARM there are some symbols which are linked in relocatable code section, then perf can't parse symbols any more from /proc/kallsyms, and this patch fixes the problem. Cc: Russell King Cc: linux-arm-kernel at lists.infradead.org Cc: Michal Marek Acked-by: Rusty Russell Signed-off-by: Ming Lei --- scripts/kallsyms.c | 12 +++++++++++- scripts/link-vmlinux.sh | 2 ++ 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index 487ac6f..9a11f9f 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -55,6 +55,7 @@ static struct sym_entry *table; static unsigned int table_size, table_cnt; static int all_symbols = 0; static char symbol_prefix_char = '\0'; +static unsigned long long kernel_start_addr = 0; int token_profit[0x10000]; @@ -65,7 +66,10 @@ unsigned char best_table_len[256]; static void usage(void) { - fprintf(stderr, "Usage: kallsyms [--all-symbols] [--symbol-prefix=] < in.map > out.S\n"); + fprintf(stderr, "Usage: kallsyms [--all-symbols] " + "[--symbol-prefix=] " + "[--page-offset=] " + "< in.map > out.S\n"); exit(1); } @@ -194,6 +198,9 @@ static int symbol_valid(struct sym_entry *s) int i; int offset = 1; + if (s->addr < kernel_start_addr) + return 0; + /* skip prefix char */ if (symbol_prefix_char && *(s->sym + 1) == symbol_prefix_char) offset++; @@ -646,6 +653,9 @@ int main(int argc, char **argv) if ((*p == '"' && *(p+2) == '"') || (*p == '\'' && *(p+2) == '\'')) p++; symbol_prefix_char = *p; + } else if (strncmp(argv[i], "--page-offset=", 14) == 0) { + const char *p = &argv[i][14]; + kernel_start_addr = strtoull(p, NULL, 16); } else usage(); } diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 0149949..32b10f5 100644 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -82,6 +82,8 @@ kallsyms() kallsymopt="${kallsymopt} --all-symbols" fi + kallsymopt="${kallsymopt} --page-offset=$CONFIG_PAGE_OFFSET" + local aflags="${KBUILD_AFLAGS} ${KBUILD_AFLAGS_KERNEL} \ ${NOSTDINC_FLAGS} ${LINUXINCLUDE} ${KBUILD_CPPFLAGS}" -- 1.7.9.5