Messages in this thread Patch in this message |  | | From | Borislav Petkov <> | Subject | [PATCH 5/7] EDAC, mce_amd: Convert to seq_buf | Date | Fri, 25 Aug 2017 12:24:09 +0200 |
| |
From: Borislav Petkov <bp@suse.de>
Convert the part which decodes the error description to the sequence buffer facility and thus save ourselves the many printk() invocations building the decoded string.
Also, use a genpool for the string buffers to handle concurrent invocations (and atomic context).
Signed-off-by: Borislav Petkov <bp@suse.de> --- drivers/edac/mce_amd.c | 215 +++++++++++++++++++++++++++++-------------------- 1 file changed, 127 insertions(+), 88 deletions(-)
diff --git a/drivers/edac/mce_amd.c b/drivers/edac/mce_amd.c index a11a671c7a38..b7c1f8f7e871 100644 --- a/drivers/edac/mce_amd.c +++ b/drivers/edac/mce_amd.c @@ -1,3 +1,5 @@ +#include <linux/genalloc.h> +#include <linux/seq_buf.h> #include <linux/module.h> #include <linux/slab.h> @@ -34,6 +36,16 @@ void amd_unregister_ecc_decoder(void (*f)(int, struct mce *)) } EXPORT_SYMBOL_GPL(amd_unregister_ecc_decoder); +/* 128 because, well, nice and round - two cachelines. */ +#define ELEM_ORDER 7 +#define ELEM_SIZE (1 << 7) +#define DEC_POOL_SIZE (2 * PAGE_SIZE) + +static char __err_buf[DEC_POOL_SIZE]; +static struct gen_pool *dec_pool; + +static struct seq_buf sb; + /* * string representation for the different MCA reported error types, see F3x48 * or MSR0000_0411. @@ -315,9 +327,9 @@ static bool f12h_mc0_mce(u16 ec, u8 xec) ret = true; if (ll == LL_L2) - pr_cont("during L1 linefill from L2.\n"); + seq_buf_printf(&sb, "during L1 linefill from L2.\n"); else if (ll == LL_L1) - pr_cont("Data/Tag %s error.\n", R4_MSG(ec)); + seq_buf_printf(&sb, "Data/Tag %s error.\n", R4_MSG(ec)); else ret = false; } @@ -327,7 +339,7 @@ static bool f12h_mc0_mce(u16 ec, u8 xec) static bool f10h_mc0_mce(u16 ec, u8 xec) { if (R4(ec) == R4_GEN && LL(ec) == LL_L1) { - pr_cont("during data scrub.\n"); + seq_buf_printf(&sb, "during data scrub.\n"); return true; } return f12h_mc0_mce(ec, xec); @@ -336,7 +348,7 @@ static bool f10h_mc0_mce(u16 ec, u8 xec) static bool k8_mc0_mce(u16 ec, u8 xec) { if (BUS_ERROR(ec)) { - pr_cont("during system linefill.\n"); + seq_buf_printf(&sb, "during system linefill.\n"); return true; } @@ -356,14 +368,14 @@ static bool cat_mc0_mce(u16 ec, u8 xec) switch (r4) { case R4_DRD: case R4_DWR: - pr_cont("Data/Tag parity error due to %s.\n", - (r4 == R4_DRD ? "load/hw prf" : "store")); + seq_buf_printf(&sb, "Data/Tag parity error due to %s.\n", + (r4 == R4_DRD ? "load/hw prf" : "store")); break; case R4_EVICT: - pr_cont("Copyback parity error on a tag miss.\n"); + seq_buf_printf(&sb, "Copyback parity error on a tag miss.\n"); break; case R4_SNOOP: - pr_cont("Tag parity error during snoop.\n"); + seq_buf_printf(&sb, "Tag parity error during snoop.\n"); break; default: ret = false; @@ -373,17 +385,17 @@ static bool cat_mc0_mce(u16 ec, u8 xec) if ((II(ec) != II_MEM && II(ec) != II_IO) || LL(ec) != LL_LG) return false; - pr_cont("System read data error on a "); + seq_buf_printf(&sb, "System read data error on a "); switch (r4) { case R4_RD: - pr_cont("TLB reload.\n"); + seq_buf_printf(&sb, "TLB reload.\n"); break; case R4_DWR: - pr_cont("store.\n"); + seq_buf_printf(&sb, "store.\n"); break; case R4_DRD: - pr_cont("load.\n"); + seq_buf_printf(&sb, "load.\n"); break; default: ret = false; @@ -403,28 +415,28 @@ static bool f15h_mc0_mce(u16 ec, u8 xec) switch (xec) { case 0x0: - pr_cont("Data Array access error.\n"); + seq_buf_printf(&sb, "Data Array access error.\n"); break; case 0x1: - pr_cont("UC error during a linefill from L2/NB.\n"); + seq_buf_printf(&sb, "UC error during a linefill from L2/NB.\n"); break; case 0x2: case 0x11: - pr_cont("STQ access error.\n"); + seq_buf_printf(&sb, "STQ access error.\n"); break; case 0x3: - pr_cont("SCB access error.\n"); + seq_buf_printf(&sb, "SCB access error.\n"); break; case 0x10: - pr_cont("Tag error.\n"); + seq_buf_printf(&sb, "Tag error.\n"); break; case 0x12: - pr_cont("LDQ access error.\n"); + seq_buf_printf(&sb, "LDQ access error.\n"); break; default: @@ -433,12 +445,12 @@ static bool f15h_mc0_mce(u16 ec, u8 xec) } else if (BUS_ERROR(ec)) { if (!xec) - pr_cont("System Read Data Error.\n"); + seq_buf_printf(&sb, "System Read Data Error.\n"); else - pr_cont(" Internal error condition type %d.\n", xec); + seq_buf_printf(&sb, " Internal error condition type %d.\n", xec); } else if (INT_ERROR(ec)) { if (xec <= 0x1f) - pr_cont("Hardware Assert.\n"); + seq_buf_printf(&sb, "Hardware Assert.\n"); else ret = false; @@ -453,13 +465,13 @@ static void decode_mc0_mce(struct mce *m) u16 ec = EC(m->status); u8 xec = XEC(m->status, xec_mask); - pr_emerg(HW_ERR "MC0 Error: "); + seq_buf_printf(&sb, HW_ERR "MC0 Error: "); /* TLB error signatures are the same across families */ if (TLB_ERROR(ec)) { if (TT(ec) == TT_DATA) { - pr_cont("%s TLB %s.\n", LL_MSG(ec), - ((xec == 2) ? "locked miss" + seq_buf_printf(&sb, "%s TLB %s.\n", LL_MSG(ec), + ((xec == 2) ? "locked miss" : (xec ? "multimatch" : "parity"))); return; } @@ -478,19 +490,19 @@ static bool k8_mc1_mce(u16 ec, u8 xec) return false; if (ll == 0x2) - pr_cont("during a linefill from L2.\n"); + seq_buf_printf(&sb, "during a linefill from L2.\n"); else if (ll == 0x1) { switch (R4(ec)) { case R4_IRD: - pr_cont("Parity error during data load.\n"); + seq_buf_printf(&sb, "Parity error during data load.\n"); break; case R4_EVICT: - pr_cont("Copyback Parity/Victim error.\n"); + seq_buf_printf(&sb, "Copyback Parity/Victim error.\n"); break; case R4_SNOOP: - pr_cont("Tag Snoop error.\n"); + seq_buf_printf(&sb, "Tag Snoop error.\n"); break; default: @@ -515,13 +527,13 @@ static bool cat_mc1_mce(u16 ec, u8 xec) return false; if (r4 == R4_IRD) - pr_cont("Data/tag array parity error for a tag hit.\n"); + seq_buf_printf(&sb, "Data/tag array parity error for a tag hit.\n"); else if (r4 == R4_SNOOP) - pr_cont("Tag error during snoop/victimization.\n"); + seq_buf_printf(&sb, "Tag error during snoop/victimization.\n"); else if (xec == 0x0) - pr_cont("Tag parity error from victim castout.\n"); + seq_buf_printf(&sb, "Tag parity error from victim castout.\n"); else if (xec == 0x2) - pr_cont("Microcode patch RAM parity error.\n"); + seq_buf_printf(&sb, "Microcode patch RAM parity error.\n"); else ret = false; @@ -537,19 +549,19 @@ static bool f15h_mc1_mce(u16 ec, u8 xec) switch (xec) { case 0x0 ... 0xa: - pr_cont("%s.\n", f15h_mc1_mce_desc[xec]); + seq_buf_printf(&sb, "%s.\n", f15h_mc1_mce_desc[xec]); break; case 0xd: - pr_cont("%s.\n", f15h_mc1_mce_desc[xec-2]); + seq_buf_printf(&sb, "%s.\n", f15h_mc1_mce_desc[xec-2]); break; case 0x10: - pr_cont("%s.\n", f15h_mc1_mce_desc[xec-4]); + seq_buf_printf(&sb, "%s.\n", f15h_mc1_mce_desc[xec-4]); break; case 0x11 ... 0x15: - pr_cont("Decoder %s parity error.\n", f15h_mc1_mce_desc[xec-4]); + seq_buf_printf(&sb, "Decoder %s parity error.\n", f15h_mc1_mce_desc[xec-4]); break; default: @@ -563,18 +575,18 @@ static void decode_mc1_mce(struct mce *m) u16 ec = EC(m->status); u8 xec = XEC(m->status, xec_mask); - pr_emerg(HW_ERR "MC1 Error: "); + seq_buf_printf(&sb, HW_ERR "MC1 Error: "); if (TLB_ERROR(ec)) - pr_cont("%s TLB %s.\n", LL_MSG(ec), - (xec ? "multimatch" : "parity error")); + seq_buf_printf(&sb, "%s TLB %s.\n", LL_MSG(ec), + (xec ? "multimatch" : "parity error")); else if (BUS_ERROR(ec)) { bool k8 = (boot_cpu_data.x86 == 0xf && (m->status & BIT_64(58))); - pr_cont("during %s.\n", (k8 ? "system linefill" : "NB data read")); + seq_buf_printf(&sb, "during %s.\n", (k8 ? "system linefill" : "NB data read")); } else if (INT_ERROR(ec)) { if (xec <= 0x3f) - pr_cont("Hardware Assert.\n"); + seq_buf_printf(&sb, "Hardware Assert.\n"); else goto wrong_mc1_mce; } else if (fam_ops->mc1_mce(ec, xec)) @@ -593,27 +605,27 @@ static bool k8_mc2_mce(u16 ec, u8 xec) bool ret = true; if (xec == 0x1) - pr_cont(" in the write data buffers.\n"); + seq_buf_printf(&sb, " in the write data buffers.\n"); else if (xec == 0x3) - pr_cont(" in the victim data buffers.\n"); + seq_buf_printf(&sb, " in the victim data buffers.\n"); else if (xec == 0x2 && MEM_ERROR(ec)) - pr_cont(": %s error in the L2 cache tags.\n", R4_MSG(ec)); + seq_buf_printf(&sb, ": %s error in the L2 cache tags.\n", R4_MSG(ec)); else if (xec == 0x0) { if (TLB_ERROR(ec)) - pr_cont("%s error in a Page Descriptor Cache or Guest TLB.\n", - TT_MSG(ec)); + seq_buf_printf(&sb, "%s error in a Page Descriptor Cache or Guest TLB.\n", + TT_MSG(ec)); else if (BUS_ERROR(ec)) - pr_cont(": %s/ECC error in data read from NB: %s.\n", - R4_MSG(ec), PP_MSG(ec)); + seq_buf_printf(&sb, ": %s/ECC error in data read from NB: %s.\n", + R4_MSG(ec), PP_MSG(ec)); else if (MEM_ERROR(ec)) { u8 r4 = R4(ec); if (r4 >= 0x7) - pr_cont(": %s error during data copyback.\n", - R4_MSG(ec)); + seq_buf_printf(&sb, ": %s error during data copyback.\n", + R4_MSG(ec)); else if (r4 <= 0x1) - pr_cont(": %s parity/ECC error during data " - "access from L2.\n", R4_MSG(ec)); + seq_buf_printf(&sb, +": %s parity/ECC error during data access from L2.\n", R4_MSG(ec)); else ret = false; } else @@ -630,24 +642,24 @@ static bool f15h_mc2_mce(u16 ec, u8 xec) if (TLB_ERROR(ec)) { if (xec == 0x0) - pr_cont("Data parity TLB read error.\n"); + seq_buf_printf(&sb, "Data parity TLB read error.\n"); else if (xec == 0x1) - pr_cont("Poison data provided for TLB fill.\n"); + seq_buf_printf(&sb, "Poison data provided for TLB fill.\n"); else ret = false; } else if (BUS_ERROR(ec)) { if (xec > 2) ret = false; - pr_cont("Error during attempted NB data read.\n"); + seq_buf_printf(&sb, "Error during attempted NB data read.\n"); } else if (MEM_ERROR(ec)) { switch (xec) { case 0x4 ... 0xc: - pr_cont("%s.\n", f15h_mc2_mce_desc[xec - 0x4]); + seq_buf_printf(&sb, "%s.\n", f15h_mc2_mce_desc[xec - 0x4]); break; case 0x10 ... 0x14: - pr_cont("%s.\n", f15h_mc2_mce_desc[xec - 0x7]); + seq_buf_printf(&sb, "%s.\n", f15h_mc2_mce_desc[xec - 0x7]); break; default: @@ -655,7 +667,7 @@ static bool f15h_mc2_mce(u16 ec, u8 xec) } } else if (INT_ERROR(ec)) { if (xec <= 0x3f) - pr_cont("Hardware Assert.\n"); + seq_buf_printf(&sb, "Hardware Assert.\n"); else ret = false; } @@ -672,29 +684,29 @@ static bool f16h_mc2_mce(u16 ec, u8 xec) switch (xec) { case 0x04 ... 0x05: - pr_cont("%cBUFF parity error.\n", (r4 == R4_RD) ? 'I' : 'O'); + seq_buf_printf(&sb, "%cBUFF parity error.\n", (r4 == R4_RD) ? 'I' : 'O'); break; case 0x09 ... 0x0b: case 0x0d ... 0x0f: - pr_cont("ECC error in L2 tag (%s).\n", - ((r4 == R4_GEN) ? "BankReq" : - ((r4 == R4_SNOOP) ? "Prb" : "Fill"))); + seq_buf_printf(&sb, "ECC error in L2 tag (%s).\n", + ((r4 == R4_GEN) ? "BankReq" : + ((r4 == R4_SNOOP) ? "Prb" : "Fill"))); break; case 0x10 ... 0x19: case 0x1b: - pr_cont("ECC error in L2 data array (%s).\n", - (((r4 == R4_RD) && !(xec & 0x3)) ? "Hit" : - ((r4 == R4_GEN) ? "Attr" : - ((r4 == R4_EVICT) ? "Vict" : "Fill")))); + seq_buf_printf(&sb, "ECC error in L2 data array (%s).\n", + (((r4 == R4_RD) && !(xec & 0x3)) ? "Hit" : + ((r4 == R4_GEN) ? "Attr" : + ((r4 == R4_EVICT) ? "Vict" : "Fill")))); break; case 0x1c ... 0x1d: case 0x1f: - pr_cont("Parity error in L2 attribute bits (%s).\n", - ((r4 == R4_RD) ? "Hit" : - ((r4 == R4_GEN) ? "Attr" : "Fill"))); + seq_buf_printf(&sb, "Parity error in L2 attribute bits (%s).\n", + ((r4 == R4_RD) ? "Hit" : + ((r4 == R4_GEN) ? "Attr" : "Fill"))); break; default: @@ -709,10 +721,10 @@ static void decode_mc2_mce(struct mce *m) u16 ec = EC(m->status); u8 xec = XEC(m->status, xec_mask); - pr_emerg(HW_ERR "MC2 Error: "); + seq_buf_printf(&sb, HW_ERR "MC2 Error: "); if (!fam_ops->mc2_mce(ec, xec)) - pr_cont(HW_ERR "Corrupted MC2 MCE info?\n"); + pr_emerg(HW_ERR "Corrupted MC2 MCE info?\n"); } static void decode_mc3_mce(struct mce *m) @@ -726,7 +738,7 @@ static void decode_mc3_mce(struct mce *m) return; } - pr_emerg(HW_ERR "MC3 Error"); + seq_buf_printf(&sb, HW_ERR "MC3 Error"); if (xec == 0x0) { u8 r4 = R4(ec); @@ -734,7 +746,7 @@ static void decode_mc3_mce(struct mce *m) if (!BUS_ERROR(ec) || (r4 != R4_DRD && r4 != R4_DWR)) goto wrong_mc3_mce; - pr_cont(" during %s.\n", R4_MSG(ec)); + seq_buf_printf(&sb, " during %s.\n", R4_MSG(ec)); } else goto wrong_mc3_mce; @@ -752,7 +764,7 @@ static void decode_mc4_mce(struct mce *m) u8 xec = XEC(m->status, 0x1f); u8 offset = 0; - pr_emerg(HW_ERR "MC4 Error (node %d): ", node_id); + seq_buf_printf(&sb, HW_ERR "MC4 Error (node %d): ", node_id); switch (xec) { case 0x0 ... 0xe: @@ -763,7 +775,7 @@ static void decode_mc4_mce(struct mce *m) if (fam == 0x11) goto wrong_mc4_mce; - pr_cont("%s.\n", mc4_mce_desc[xec]); + seq_buf_printf(&sb, "%s.\n", mc4_mce_desc[xec]); if (decode_dram_ecc) decode_dram_ecc(node_id, m); @@ -773,16 +785,16 @@ static void decode_mc4_mce(struct mce *m) case 0xf: if (TLB_ERROR(ec)) - pr_cont("GART Table Walk data error.\n"); + seq_buf_printf(&sb, "GART Table Walk data error.\n"); else if (BUS_ERROR(ec)) - pr_cont("DMA Exclusion Vector Table Walk error.\n"); + seq_buf_printf(&sb, "DMA Exclusion Vector Table Walk error.\n"); else goto wrong_mc4_mce; return; case 0x19: if (fam == 0x15 || fam == 0x16) - pr_cont("Compute Unit Data Error.\n"); + seq_buf_printf(&sb, "Compute Unit Data Error.\n"); else goto wrong_mc4_mce; return; @@ -795,7 +807,7 @@ static void decode_mc4_mce(struct mce *m) goto wrong_mc4_mce; } - pr_cont("%s.\n", mc4_mce_desc[xec - offset]); + seq_buf_printf(&sb, "%s.\n", mc4_mce_desc[xec - offset]); return; wrong_mc4_mce: @@ -811,20 +823,20 @@ static void decode_mc5_mce(struct mce *m) if (fam == 0xf || fam == 0x11) goto wrong_mc5_mce; - pr_emerg(HW_ERR "MC5 Error: "); + seq_buf_printf(&sb, HW_ERR "MC5 Error: "); if (INT_ERROR(ec)) { if (xec <= 0x1f) { - pr_cont("Hardware Assert.\n"); + seq_buf_printf(&sb, "Hardware Assert.\n"); return; } else goto wrong_mc5_mce; } if (xec == 0x0 || xec == 0xc) - pr_cont("%s.\n", mc5_mce_desc[xec]); + seq_buf_printf(&sb, "%s.\n", mc5_mce_desc[xec]); else if (xec <= 0xd) - pr_cont("%s parity error.\n", mc5_mce_desc[xec]); + seq_buf_printf(&sb, "%s parity error.\n", mc5_mce_desc[xec]); else goto wrong_mc5_mce; @@ -838,12 +850,12 @@ static void decode_mc6_mce(struct mce *m) { u8 xec = XEC(m->status, xec_mask); - pr_emerg(HW_ERR "MC6 Error: "); + seq_buf_printf(&sb, HW_ERR "MC6 Error: "); if (xec > 0x5) goto wrong_mc6_mce; - pr_cont("%s parity error.\n", mc6_mce_desc[xec]); + seq_buf_printf(&sb, "%s parity error.\n", mc6_mce_desc[xec]); return; wrong_mc6_mce: @@ -871,13 +883,13 @@ static void decode_smca_error(struct mce *m) bank_type = hwid->bank_type; ip_name = smca_get_long_name(bank_type); - pr_emerg(HW_ERR "%s Extended Error Code: %d\n", ip_name, xec); + seq_buf_printf(&sb, HW_ERR "%s Extended Error Code: %d\n", ip_name, xec); /* Only print the decode of valid error codes */ if (xec < smca_mce_descs[bank_type].num_descs && (hwid->xec_bitmap & BIT_ULL(xec))) { - pr_emerg(HW_ERR "%s Error: ", ip_name); - pr_cont("%s.\n", smca_mce_descs[bank_type].descs[xec]); + seq_buf_printf(&sb, HW_ERR "%s Error: ", ip_name); + seq_buf_printf(&sb, "%s.\n", smca_mce_descs[bank_type].descs[xec]); } if (bank_type == SMCA_UMC && xec == 0 && decode_dram_ecc) @@ -944,10 +956,21 @@ amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data) struct mce *m = (struct mce *)data; unsigned int fam = x86_family(m->cpuid); int ecc; + char *dec_buf; if (amd_filter_mce(m)) return NOTIFY_STOP; + dec_buf = (void *)gen_pool_alloc(dec_pool, ELEM_SIZE); + if (!dec_buf) { + pr_warn("Decode buffer full!\n"); + return NOTIFY_STOP; + } + + /* \0 terminated */ + seq_buf_init(&sb, dec_buf, ELEM_SIZE); + seq_buf_clear_buf(&sb); + pr_emerg(HW_ERR "%s\n", decode_error_status(m)); pr_emerg(HW_ERR "CPU:%d (%x:%x:%x) MC%d_STATUS[%s|%s|%s|%s|%s", @@ -1044,6 +1067,10 @@ amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data) err_code: amd_decode_err_code(m->status & 0xffff); + pr_emerg("%.*s\n", (int)sb.len, sb.buffer); + + gen_pool_free(dec_pool, (unsigned long)dec_buf, ELEM_SIZE); + return NOTIFY_STOP; } @@ -1055,6 +1082,7 @@ static struct notifier_block amd_mce_dec_nb = { static int __init mce_amd_init(void) { struct cpuinfo_x86 *c = &boot_cpu_data; + int ret; if (c->x86_vendor != X86_VENDOR_AMD) return -ENODEV; @@ -1122,6 +1150,16 @@ static int __init mce_amd_init(void) goto err_out; } + dec_pool = gen_pool_create(ELEM_ORDER, -1); + if (!dec_pool) + goto err_out; + + ret = gen_pool_add(dec_pool, (unsigned long)__err_buf, DEC_POOL_SIZE, -1); + if (ret) { + gen_pool_destroy(dec_pool); + goto err_out; + } + pr_info("MCE: In-kernel MCE decoding enabled.\n"); mce_register_decode_chain(&amd_mce_dec_nb); @@ -1140,6 +1178,7 @@ static void __exit mce_amd_exit(void) { mce_unregister_decode_chain(&amd_mce_dec_nb); kfree(fam_ops); + gen_pool_destroy(dec_pool); } MODULE_DESCRIPTION("AMD MCE decoder"); -- 2.13.0
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