From: Michael Ellerman <mpe@ellerman.id.au>
To: <linuxppc-dev@lists.ozlabs.org>
Subject: [PATCH] powerpc/64e: Fix secondary thread bringup for ELFv2 kernels
Date: Tue, 1 Aug 2023 20:26:50 +1000 [thread overview]
Message-ID: <20230801102650.48705-1-mpe@ellerman.id.au> (raw)
When booting on e6500 with an ELF v2 ABI kernel, the secondary threads do
not start correctly:
[ 0.051118] smp: Bringing up secondary CPUs ...
[ 5.072700] Processor 1 is stuck.
This occurs because the startup code is written to use function
descriptors when loading the entry point for the secondary threads. When
building with ELF v2 ABI there are no function descriptors, and the code
loads junk values for the entry point address.
Fix it by using ppc_function_entry() in C, and DOTSYM() in asm, both of
which work correctly for ELF v2 ABI as well as ELF v1 ABI kernels.
Fixes: 8c5fa3b5c4df ("powerpc/64: Make ELFv2 the default for big-endian builds")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
arch/powerpc/kernel/head_64.S | 3 +--
arch/powerpc/platforms/85xx/smp.c | 2 +-
2 files changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index f132d8704263..6440b1bb332a 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -375,8 +375,7 @@ _GLOBAL(generic_secondary_smp_init)
beq 20f
/* start the specified thread */
- LOAD_REG_ADDR(r5, fsl_secondary_thread_init)
- ld r4, 0(r5)
+ LOAD_REG_ADDR(r5, DOTSYM(fsl_secondary_thread_init))
bl book3e_start_thread
/* stop the current thread */
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
index 9c43cf32f4c9..40aa58206888 100644
--- a/arch/powerpc/platforms/85xx/smp.c
+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -180,7 +180,7 @@ static void wake_hw_thread(void *info)
unsigned long inia;
int cpu = *(const int *)info;
- inia = *(unsigned long *)fsl_secondary_thread_init;
+ inia = ppc_function_entry(fsl_secondary_thread_init);
book3e_start_thread(cpu_thread_in_core(cpu), inia);
}
#endif
--
2.41.0
reply other threads:[~2023-08-01 10:28 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=20230801102650.48705-1-mpe@ellerman.id.au \
--to=mpe@ellerman.id.au \
--cc=linuxppc-dev@lists.ozlabs.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.