On 9/18/24 10:46 AM, Muhammad Usama Anjum wrote:
On 9/17/24 6:56 AM, Shuah Khan wrote:
On 9/16/24 00:32, Muhammad Usama Anjum wrote:
On 9/12/24 8:44 PM, Shuah Khan wrote:
On 9/12/24 04:31, Muhammad Usama Anjum wrote:
The value of __NR_userfaultfd was changed to 282 when asm-generic/unistd.h was included. It makes the test to fail every time as the correct number of this syscall on x86_64 is 323. Fix the header to asm/unistd.h.
"please elaborate every time" - I just built on my x86_64 and built just fine.
The build isn't broken.
I am not saying this isn't a problem, it is good to understand why and how it is failing before making the change.
I mean to say that the test is failing at run time because the correct userfaultfd syscall isn't being found with __NR_userfaultfd = 282. _NR_userfaultfd's value depends on the header. When asm-generic/unistd.h is included, its value (282) is wrong. I've tested on x86_64.
Okay - how do you know this is wrong? can you provide more details.
git grep _NR_userfaultfd include/uapi/asm-generic/unistd.h:#define __NR_userfaultfd 282 include/uapi/asm-generic/unistd.h:__SYSCALL(__NR_userfaultfd, sys_userfaultfd) tools/include/uapi/asm-generic/unistd.h:#define __NR_userfaultfd 282
The fix is simple. Add the correct header which has _NR_userfaultfd = 323.
grep -rnIF "#define __NR_userfaultfd" tools/include/uapi/asm-generic/unistd.h:681:#define __NR_userfaultfd 282 arch/x86/include/generated/uapi/asm/unistd_32.h:374:#define __NR_userfaultfd 374 arch/x86/include/generated/uapi/asm/unistd_64.h:327:#define __NR_userfaultfd 323 arch/x86/include/generated/uapi/asm/unistd_x32.h:282:#define __NR_userfaultfd (__X32_SYSCALL_BIT + 323) arch/arm/include/generated/uapi/asm/unistd-eabi.h:347:#define __NR_userfaultfd (__NR_SYSCALL_BASE + 388) arch/arm/include/generated/uapi/asm/unistd-oabi.h:359:#define __NR_userfaultfd (__NR_SYSCALL_BASE + 388) include/uapi/asm-generic/unistd.h:681:#define __NR_userfaultfd 282
The number is dependent on the architecture. The above data shows that: x86 374 x86_64 323
I'm unable to find the history of why it is set to 282 in unistd.h and when this problem happened.
Does anybody has understanding of this?
I need more details on this number.
thanks, -- Shuah