All of lore.kernel.org
 help / color / mirror / Atom feed
From: Song Liu <song@kernel.org>
To: bpf@vger.kernel.org, netdev@vger.kernel.org
Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org,
	kernel-team@meta.com, song@kernel.org,
	Jakub Kicinski <kuba@kernel.org>
Subject: [PATCH bpf-next] selftests/bpf: Fix verifier_bpf_fastcall
Date: Fri, 28 Mar 2025 12:31:24 -0700	[thread overview]
Message-ID: <20250328193124.808784-1-song@kernel.org> (raw)

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 9d7de2aa8b41 ("x86/percpu/64: Use relative percpu offsets")
[2] commit 01c7bc5198e9 ("x86/smp: Move cpu number to percpu hot section")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
---
 tools/testing/selftests/bpf/progs/verifier_bpf_fastcall.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/bpf/progs/verifier_bpf_fastcall.c b/tools/testing/selftests/bpf/progs/verifier_bpf_fastcall.c
index a9be6ae49454..c258b0722e04 100644
--- a/tools/testing/selftests/bpf/progs/verifier_bpf_fastcall.c
+++ b/tools/testing/selftests/bpf/progs/verifier_bpf_fastcall.c
@@ -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 */
-- 
2.47.1


             reply	other threads:[~2025-03-28 19:31 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-03-28 19:31 Song Liu [this message]
2025-03-30 23:40 ` [PATCH bpf-next] selftests/bpf: Fix verifier_bpf_fastcall patchwork-bot+netdevbpf

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20250328193124.808784-1-song@kernel.org \
    --to=song@kernel.org \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=kernel-team@meta.com \
    --cc=kuba@kernel.org \
    --cc=netdev@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.