kdb: Get rid of custom debug heap allocator

Currently the only user for debug heap is kdbnearsym() which can be
modified to rather use statically allocated buffer for symbol name as
per it's current usage. So do that and hence remove custom debug heap
allocator.

Note that this change puts a restriction on kdbnearsym() callers to
carefully use shared namebuf such that a caller should consume the symbol
returned immediately prior to another call to fetch a different symbol.

Also, this change uses standard KSYM_NAME_LEN macro for namebuf
allocation instead of local variable: knt1_size which should avoid any
conflicts caused by changes to KSYM_NAME_LEN macro value.

This change has been tested using kgdbtest on arm64 which doesn't show
any regressions.

Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20210714055620.369915-1-sumit.garg@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

1 files changed, 0 insertions, 5 deletions

diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h
index 170c69aedebb..8dbc840113c9 100644
--- a/kernel/debug/kdb/kdb_private.h
+++ b/kernel/debug/kdb/kdb_private.h
@@ -109,7 +109,6 @@ extern int kdbgetaddrarg(int, const char **, int*, unsigned long *,
 			 long *, char **);
 extern int kdbgetsymval(const char *, kdb_symtab_t *);
 extern int kdbnearsym(unsigned long, kdb_symtab_t *);
-extern void kdbnearsym_cleanup(void);
 extern char *kdb_strdup(const char *str, gfp_t type);
 extern void kdb_symbol_print(unsigned long, const kdb_symtab_t *, unsigned int);
 
@@ -233,10 +232,6 @@ extern struct task_struct *kdb_curr_task(int);
 
 #define GFP_KDB (in_dbg_master() ? GFP_ATOMIC : GFP_KERNEL)
 
-extern void *debug_kmalloc(size_t size, gfp_t flags);
-extern void debug_kfree(void *);
-extern void debug_kusage(void);
-
 extern struct task_struct *kdb_current_task;
 extern struct pt_regs *kdb_current_regs;