From: Fenghua Yu Date: Fri, 30 May 2014 21:59:24 +0000 (-0700) Subject: x86/xsaves: Clean up code in xstate offsets computation in xsave area X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=8ff925e10f2c72680918b95173ef4f8bb982d59e;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git x86/xsaves: Clean up code in xstate offsets computation in xsave area This patch cleans up some code in xstate offsets computation in xsave area: 1. It changes xstate_comp_offsets as an array. This avoids possible NULL pointer caused by possible kmalloc() failure during boot time. 2. It changes the global variable xstate_comp_sizes to a local variable because it is used only in setup_xstate_comp(). 3. It adds missing offsets for FP and SSE in xsave area. Signed-off-by: Fenghua Yu Link: http://lkml.kernel.org/r/1401387164-43416-17-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin --- diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c index a6cb8233f628..940b142cc11f 100644 --- a/arch/x86/kernel/xsave.c +++ b/arch/x86/kernel/xsave.c @@ -26,7 +26,7 @@ struct xsave_struct *init_xstate_buf; static struct _fpx_sw_bytes fx_sw_reserved, fx_sw_reserved_ia32; static unsigned int *xstate_offsets, *xstate_sizes; -static unsigned int *xstate_comp_offsets, *xstate_comp_sizes; +static unsigned int xstate_comp_offsets[sizeof(pcntxt_mask)*8]; static unsigned int xstate_features; /* @@ -491,11 +491,16 @@ static void __init setup_xstate_features(void) */ void setup_xstate_comp(void) { + unsigned int xstate_comp_sizes[sizeof(pcntxt_mask)*8]; int i; - xstate_comp_offsets = kmalloc(xstate_features * sizeof(int), - GFP_KERNEL); - xstate_comp_sizes = kmalloc(xstate_features * sizeof(int), GFP_KERNEL); + /* + * The FP xstates and SSE xstates are legacy states. They are always + * in the fixed offsets in the xsave area in either compacted form + * or standard form. + */ + xstate_comp_offsets[0] = 0; + xstate_comp_offsets[1] = offsetof(struct i387_fxsave_struct, xmm_space); if (!cpu_has_xsaves) { for (i = 2; i < xstate_features; i++) {