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selftests/bpf: Fix verifier_bpf_fastcall test

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Commit [1] moves percpu data on x86 from address 0x000... to address
0xfff...

Before [1]:

159020: 0000000000030700     0 OBJECT  GLOBAL DEFAULT   23 pcpu_hot

After [1]:

152602: ffffffff83a3e034     4 OBJECT  GLOBAL DEFAULT   35 pcpu_hot

As a result, verifier_bpf_fastcall tests should now expect a negative
value for pcpu_hot, IOW, the disassemble should show "r=" instead of
"w=".

Fix this in the test.

Note that, a later change created a new variable "cpu_number" for
bpf_get_smp_processor_id() [2]. The inlining logic is updated properly
as part of this change, so there is no need to fix anything on the
kernel side.

[1] commit 9d7de2aa8b ("x86/percpu/64: Use relative percpu offsets")
[2] commit 01c7bc5198 ("x86/smp: Move cpu number to percpu hot section")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20250328193124.808784-1-song@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Song Liu
2025-03-28 12:31:24 -07:00
committed by Alexei Starovoitov
parent 00387808d3
commit 14d84357a0
1 changed files with 3 additions and 3 deletions
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6
tools/testing/selftests/bpf/progs/verifier_bpf_fastcall.c
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@@ -12,7 +12,7 @@ SEC("raw_tp")
__arch_x86_64
__log_level(4) __msg("stack depth 8")
__xlated("4: r5 = 5")
__xlated("5: w0 = ")
__xlated("5: r0 = ")
__xlated("6: r0 = &(void __percpu *)(r0)")
__xlated("7: r0 = *(u32 *)(r0 +0)")
__xlated("8: exit")
@@ -704,7 +704,7 @@ SEC("raw_tp")
__arch_x86_64
__log_level(4) __msg("stack depth 32+0")
__xlated("2: r1 = 1")
__xlated("3: w0 =")
__xlated("3: r0 =")
__xlated("4: r0 = &(void __percpu *)(r0)")
__xlated("5: r0 = *(u32 *)(r0 +0)")
/* bpf_loop params setup */
@@ -753,7 +753,7 @@ __arch_x86_64
__log_level(4) __msg("stack depth 40+0")
/* call bpf_get_smp_processor_id */
__xlated("2: r1 = 42")
__xlated("3: w0 =")
__xlated("3: r0 =")
__xlated("4: r0 = &(void __percpu *)(r0)")
__xlated("5: r0 = *(u32 *)(r0 +0)")
/* call bpf_get_prandom_u32 */