On Thu, Jan 31, 2019 at 10:20:13PM +0100, Borislav Petkov wrote: >On Thu, Jan 31, 2019 at 04:39:46PM +0800, Chao Fan wrote: >> __puthex() is the only method to print value in compressed boot stage. >> But in i386-PAE, sizeof(unsigned long) is 4, so that the value of >> 64-bit is cut and print a wrong value. That will mislead developers >> when debugging. >> Expand the type to unsigned long long to print the right value. >> >> Suggested-by: Ruan Shiyang <ruansy.f...@cn.fujitsu.com> >> Signed-off-by: Chao Fan <fanc.f...@cn.fujitsu.com> >> --- >> Here is my PATCHSET: >> https://lkml.org/lkml/2019/1/23/266 >> When debugging, I need to print the memory address and length then >> check the value is right or not. They may exceed 4G in i386-PAE, >> but the upper half was cut because unsigned long is not enough. >> >> A same condition fix after start_kernel() in ACPI has been merged: >> commit b9ced18acf68dffebe6888c7ec765a2b1db7a039 >> Author: Chao Fan <fanc.f...@cn.fujitsu.com> >> Date: Wed Dec 26 11:34:50 2018 +0800 >> >> ACPI: NUMA: Use correct type for printing addresses on i386-PAE >> --- >> arch/x86/boot/compressed/misc.c | 2 +- >> arch/x86/boot/compressed/misc.h | 2 +- >> 2 files changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/arch/x86/boot/compressed/misc.c >> b/arch/x86/boot/compressed/misc.c >> index 8dd1d5ccae58..30fb8abdb154 100644 >> --- a/arch/x86/boot/compressed/misc.c >> +++ b/arch/x86/boot/compressed/misc.c >> @@ -153,7 +153,7 @@ void __putstr(const char *s) >> outb(0xff & (pos >> 1), vidport+1); >> } >> >> -void __puthex(unsigned long value) >> +void __puthex(unsigned long long value) > >Not enough because debug_putaddr() still converts it to unsigned long. >So you get (still truncated) values with 8 preceding zeroes:
Yes, so sometimes it's better to use debug_puthex(). > >input_data: 0x00000000036bf100 >input_len: 0x00000000005b694b >output: 0x0000000001000000 >output_len: 0x0000000000bfba30 >kernel_total_size: 0x0000000002c92000 >beefy: 0x00000000cafebabe > >beefy is a test variable I declared: > >u64 beefy = 0xdeadbeefcafebabe; > >If anything, there should be a separate set of helpers which take 64-bit >quantities as arguments. But I don't see any need for them now. It's not used for existing code, it's used to help developers debug. Just in my RSDP PATCHSET, I need to print the memory regions from SRAT and check the value, then I found the value of memory regions in last 2 nodes are always wrong, I though there are some problems in my code. Later I found the value was cut and neither debug_putaddr() nor debug_puthex() is enough to use, then I change them to unsigned long long in my local code and continue to debug. So I send the change as PATCH and to see if later developers need the debug tool. Thanks, Chao Fan > >-- >Regards/Gruss, > Boris. > >Good mailing practices for 400: avoid top-posting and trim the reply. > >
