6.9-stable review patch. If anyone has any objections, please let me know.
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From: Baoquan He bhe@redhat.com
commit f4af41bf177add167e39e4b0203460b1d0b531f6 upstream.
Jiri reported that the current kexec_dprintk() always prints out debugging message whenever kexec/kdmmp loading is triggered. That is not wanted. The debugging message is supposed to be printed out when 'kexec -s -d' is specified for kexec/kdump loading.
After investigating, the reason is the current kexec_dprintk() takes printk(KERN_INFO) or printk(KERN_DEBUG) depending on whether '-d' is specified. However, distros usually have defaulg log level like below:
[~]# cat /proc/sys/kernel/printk 7 4 1 7
So, even though '-d' is not specified, printk(KERN_DEBUG) also always prints out. I thought printk(KERN_DEBUG) is equal to pr_debug(), it's not.
Fix it by changing to use pr_info() instead which are expected to work.
Link: https://lkml.kernel.org/r/20240409042238.1240462-1-bhe@redhat.com Fixes: cbc2fe9d9cb2 ("kexec_file: add kexec_file flag to control debug printing") Signed-off-by: Baoquan He bhe@redhat.com Reported-by: Jiri Slaby jirislaby@kernel.org Closes: https://lore.kernel.org/all/4c775fca-5def-4a2d-8437-7130b02722a2@kernel.org Reviewed-by: Dave Young dyoung@redhat.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/linux/kexec.h | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 060835bb82d5..f31bd304df45 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -461,10 +461,8 @@ static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) {
extern bool kexec_file_dbg_print;
-#define kexec_dprintk(fmt, ...) \ - printk("%s" fmt, \ - kexec_file_dbg_print ? KERN_INFO : KERN_DEBUG, \ - ##__VA_ARGS__) +#define kexec_dprintk(fmt, arg...) \ + do { if (kexec_file_dbg_print) pr_info(fmt, ##arg); } while (0)
#else /* !CONFIG_KEXEC_CORE */ struct pt_regs;