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| author | Laurent ALFONSI <laurent.alfonsi@st.com> | 2017-04-18 17:50:16 +0200 |
|---|---|---|
| committer | Jeff Johnston <jjohnstn@redhat.com> | 2017-05-19 15:45:58 -0400 |
| commit | 9b1167219a11311dd5a3db4b6802feea2f2ee765 (patch) | |
| tree | 36ffd5c202e32f5a65a5fe3122742292dc1c9cc3 /libgloss/aarch64 | |
| parent | 9d32147e35464893987d72ffae6d900dec5f9106 (diff) | |
| download | newlib-9b1167219a11311dd5a3db4b6802feea2f2ee765.zip newlib-9b1167219a11311dd5a3db4b6802feea2f2ee765.tar.gz newlib-9b1167219a11311dd5a3db4b6802feea2f2ee765.tar.bz2 | |
ARM/AArch64: Fix GetCmdLine semihosting directivesnewlib-snapshot-20170519
When simulating arm code, the target program startup code (crt0) uses
semihosting invocations to get the command line from the simulator. The
simulator returns the command line and its size into the area passed in
parameter. (ARM 32-bit specifications :
http://infocenter.arm.com/help/topic/com.arm.doc.dui0058d/DUI0058.pdf
chapter "5.4.19 SYS_GET_CMDLINE").
The memory area pointed by the semihosting register argument is located
in .text section (usually not writtable (RX)).
If we run this code on a simulator that respects this rights properties
(qemu user-mode for instance), the command line will not be written to
the .text program memory, in particular the length of the string. The
program runs with an empty command line. This problem hasn't been seen
earlier probably because qemu user-mode is not so much used, but this can
happen with another simulator that refuse to write in a read-only segment.
With this modification, the command line can be correctly passed to the
target program.
Changes:
- libgloss/arm/crt0.S : Arguments passed to the AngelSWI_Reason_GetCmdLine
semihosting invocation are placed into .data section instead of .text
- libgloss/aarch64/crt0.S : Idem for aarch64 AngelSVC_Reason_GetCmdLine
semihosting.
Diffstat (limited to 'libgloss/aarch64')
| -rw-r--r-- | libgloss/aarch64/crt0.S | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/libgloss/aarch64/crt0.S b/libgloss/aarch64/crt0.S index ae6264d..ed4dafc 100644 --- a/libgloss/aarch64/crt0.S +++ b/libgloss/aarch64/crt0.S @@ -156,10 +156,11 @@ bl FUNCTION (_init) /* Fetch and parse the command line. */ - adr x1, .Lcmdline /* Command line descriptor. */ + ldr x1, .Lcmdline /* Command line descriptor. */ mov w0, #AngelSVC_Reason_GetCmdLine AngelSVCAsm AngelSVC ldr x8, .Lcmdline + ldr x8, [x8] mov x0, #0 /* argc */ mov x1, sp /* argv */ @@ -239,9 +240,7 @@ FUNCTION (_cpu_init_hook): .Lenvp: GEN_DWORD env .Lcmdline: - GEN_DWORD CommandLine - .dword 255 - + GEN_DWORD AngelSVCArgs /* Workspace for Angel calls. */ .data .align 3 @@ -258,3 +257,6 @@ StackBase: .dword 0 StackLimit: .dword 0 env: .dword 0 /* Dummy environment array */ CommandLine: .space 256,0 /* Maximum length of 255 chars handled. */ +AngelSVCArgs: + GEN_DWORD CommandLine + .dword 255 |