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| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2021-08-24 09:56:26 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-08-25 05:35:47 +0200 |
| commit | f5007dbf4da729baa850b33a64dc3cc53757bdf8 (patch) | |
| tree | 9e0faa1eca3f840f7e51dc50016697f26585acd2 /arch/powerpc/kernel/head_44x.S | |
| parent | powerpc/32: indirect function call use bctrl rather than blrl in ret_from_ker... (diff) | |
| download | linux-f5007dbf4da729baa850b33a64dc3cc53757bdf8.tar.xz linux-f5007dbf4da729baa850b33a64dc3cc53757bdf8.zip | |
powerpc/booke: Avoid link stack corruption in several places
Use bcl 20,31,+4 instead of bl in order to preserve link stack.
See commit c974809a26a1 ("powerpc/vdso: Avoid link stack corruption
in __get_datapage()") for details.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e9fbc285eceb720e6c0e032ef47fe8b05f669b48.1629791751.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/kernel/head_44x.S')
| -rw-r--r-- | arch/powerpc/kernel/head_44x.S | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S index ddc978a2d381..02d2928d1e01 100644 --- a/arch/powerpc/kernel/head_44x.S +++ b/arch/powerpc/kernel/head_44x.S @@ -70,7 +70,7 @@ _ENTRY(_start); * address. * r21 will be loaded with the physical runtime address of _stext */ - bl 0f /* Get our runtime address */ + bcl 20,31,$+4 /* Get our runtime address */ 0: mflr r21 /* Make it accessible */ addis r21,r21,(_stext - 0b)@ha addi r21,r21,(_stext - 0b)@l /* Get our current runtime base */ @@ -853,7 +853,7 @@ _GLOBAL(init_cpu_state) wmmucr: mtspr SPRN_MMUCR,r3 /* Put MMUCR */ sync - bl invstr /* Find our address */ + bcl 20,31,$+4 /* Find our address */ invstr: mflr r5 /* Make it accessible */ tlbsx r23,0,r5 /* Find entry we are in */ li r4,0 /* Start at TLB entry 0 */ @@ -1045,7 +1045,7 @@ head_start_47x: sync /* Find the entry we are running from */ - bl 1f + bcl 20,31,$+4 1: mflr r23 tlbsx r23,0,r23 tlbre r24,r23,0 |