BMC/Intel-BMC/linux.git/arch/sparc/include/asm/oplib_64.h, branch dev

sparc64: Fix register corruption in top-most kernel stack frame during boot.

2014-10-24T16:52:49+00:00

Meelis Roos reported that kernels built with gcc-4.9 do not boot, we eventually narrowed this down to only impacting machines using UltraSPARC-III and derivitive cpus. The crash happens right when the first user process is spawned: [ 54.451346] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004 [ 54.451346] [ 54.571516] CPU: 1 PID: 1 Comm: init Not tainted 3.16.0-rc2-00211-gd7933ab #96 [ 54.666431] Call Trace: [ 54.698453] [0000000000762f8c] panic+0xb0/0x224 [ 54.759071] [000000000045cf68] do_exit+0x948/0x960 [ 54.823123] [000000000042cbc0] fault_in_user_windows+0xe0/0x100 [ 54.902036] [0000000000404ad0] __handle_user_windows+0x0/0x10 [ 54.978662] Press Stop-A (L1-A) to return to the boot prom [ 55.050713] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004 Further investigation showed that compiling only per_cpu_patch() with an older compiler fixes the boot. Detailed analysis showed that the function is not being miscompiled by gcc-4.9, but it is using a different register allocation ordering. With the gcc-4.9 compiled function, something during the code patching causes some of the %i* input registers to get corrupted. Perhaps we have a TLB miss path into the firmware that is deep enough to cause a register window spill and subsequent restore when we get back from the TLB miss trap. Let's plug this up by doing two things: 1) Stop using the firmware stack for client interface calls into the firmware. Just use the kernel's stack. 2) As soon as we can, call into a new function "start_early_boot()" to put a one-register-window buffer between the firmware's deepest stack frame and the top-most initial kernel one. Reported-by: Meelis Roos Tested-by: Meelis Roos Signed-off-by: David S. Miller

sparc: drop use of extern for prototypes in arch/sparc/include/asm

2014-05-19T02:01:29+00:00

Drop extern for all prototypes and adjust alignment of parameters as required after the removal. In a few rare cases adjust linelength to conform to maximum 80 chars, and likewise in a few rare cases adjust alignment of parameters to static functions. Signed-off-by: Sam Ravnborg Signed-off-by: David S. Miller

sparc: fix format string argument for prom_printf()

2012-10-03T03:20:34+00:00

prom_printf() takes printf style arguments. Specifing GCC's format attribute reveals that there are several wrong usages of prom_printf(). This fixes those wrong format strings and arguments, and also leaves format attributes in order to detect similar mistakes at compile time. Signed-off-by: Akinobu Mita Cc: "David S. Miller" Cc: sparclinux@vger.kernel.org Signed-off-by: David S. Miller

sparc: Eliminate prom_stdin.

2010-12-12T22:57:53+00:00

Completely unused. Based upon a patch by Julian Calaby. Signed-off-by: David S. Miller

sparc: Write to prom console using indirect buffer.

2010-12-01T04:15:58+00:00

sparc64 systems have a restriction in that passing in buffer addressses above 4GB to prom calls is not reliable. We end up violating this when we do prom console writes, because we use an on-stack buffer to translate '\n' into '\r\n'. So instead, do this translation into an intermediate buffer, which is in the kernel image and thus below 4GB, then pass that to the PROM console write calls. On the 32-bit side we don't have to deal with any of these issues, so the new prom_console_write_buf() uses the existing prom_nbputchar() implementation. However we can now mark those routines static. Since the 64-bit side completely uses new code we can delete the putchar bits as they are now completely unused. Signed-off-by: David S. Miller

sparc: Delete prom_*getchar().

2010-11-30T22:53:05+00:00

Completely unused. Signed-off-by: David S. Miller

sparc: Pass buffer pointer all the way down to prom_{get,put}char().

2010-11-30T22:33:29+00:00

This gets us closer to being able to eliminate the use of dynamic and stack based buffers, so that we can adhere to the "no buffer addresses above 4GB" rule for PROM calls. Signed-off-by: David S. Miller

sparc: Do not export prom_nb{get,put}char().

2010-11-17T18:22:56+00:00

Never used outside of console_{32,64}.c Signed-off-by: David S. Miller

sparc64: Delete prom_setcallback().

2010-11-16T20:50:19+00:00

Unused. Signed-off-by: David S. Miller

sparc64: Unexport prom_service_exists().

2010-11-16T20:24:16+00:00

Only used by functions in misc_64.c so make it private to that file. Signed-off-by: David S. Miller